3000 word explanation or I'm calling bullshit
The Plural of Penis
The Straight Dope (
http://www.straightdope.com/columns/)
A must read imho
September 28, 2004
Abstract
What exactly is the plural of penis? I would say penises, but it seems
too simple and obvious. Is it penis, like deer, or maybe peni, like fungi?
–Sissy, Emerald Isle, NC
If you have more than one, you should be writing to Ripley’s and not to the
Straight Dope. Heck, Sissy, if you have even one, the first thing you should do
is change your name to Buddy.
In this case, your first instinct is a good one. The English-style plural is usually
acceptable and often preferred. When you don’t know what the Latin plural is
and don’t have a dictionary handy, you should choose the English-style plural
rather than try to guess. (Sometimes even dictionaries will steer you wrong;
see below). In your example, penises is a perfectly good plural of penis in English.
Many people who deal with penises professionally use the Latin-style
plural penes instead. That’s fine too, but even among urologists, penises seem
to predominate. Seems, rather. ”Penises” seems to predominate.
Guessing the plural of a Latin word is one of those things where a little learning
is a dangerous thing (but that’s still ”not one half so bad as a lot of ignorance,”
to quote Terry Pratchett). Those with entirely too much learning know that
Latin nouns are divided into five categories, called declensions. To figure out
the plural of a Latin noun without cheating (i.e., looking it up), it is necessary,
and often sufficient, to know which of the five declensions it belongs to. (There
are a few nouns, like virus, that don’t fit neatly into any of the declensions, but
more on that later). For example, you mention peni as a possible plural of penis.
The -i ending is valid for forming the plural of second-declension Latin nouns
ending in -us, but of course that doesn’t apply to penis. Part of the problem is
that when unaccented, the singular endings -us and -is tend to be pronounced
the same in English. Those with a little learning know that penus, if it were a
second declension noun like most -us nouns in Latin, would be expected to have
the plural form peni. Since penus would be pronounced the same–or almost the
same–as penis in English, the temptation is strong to use the incorrect peni as
the plural. Peni is an example of what is called pseudo-Latin, something that
looks like Latin but isn’t. A similar mistake is using porpi as the plural of porpoise,
but in that case the singular was long spelled porpus under the mistaken
impression that it was a Latin word.
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Penis is a third declension noun, not second declension. These nouns often
end in -is in the singular and -es in the plural. The English style -ises is sometimes
preferred. Hence, we have penises (half of us do, anyway), and mantises
and pelvises, but only more rarely do you see penes, mantes, and pelves, though
they are not incorrect. In many cases, only the Latin form is acceptable: We
have testes (some more than others) and crises and psychoses, but never testises,
crisises, or pyschosises.
Another group of third-declension Latin nouns, mostly borrowed from Greek,
end in -is in the singular, but the full root is not found in that form. These you
either have to learn by heart or look up. For example, the Latin plural of iris
is irides, which is acceptable in English, but I prefer irises. I like clitorises, but
the Latin form clitorides is also acceptable.
Among second declension -us nouns borrowed into English, the English style
plural -uses is often preferred to the Latin -i. Thus isthmuses and crocuses are
generally preferred, but isthmi and croci are still acceptable. For many words,
the Latin style is preferred, but the English is acceptable, as in fungi (or funguses).
Sometimes the Latin style is preferred in technical usage, while the
English style is better for the nontechnical. Mathematically speaking, ellipses
have foci, while investigations may have focuses.
Of course the English style -uses requires an extra syllable, and you have to
judge for yourself whether it’s worth it for polysyllabic words. Nuclei rolls off
the tongue easier than nucleuses, but both are acceptable. Either the long
hippopotami or the longer hippopotamuses is acceptable, but it’s easy to see
why some people are attracted to hippos. In Greek, the African pachyderm was
called a riverine horse: hippopotamos (plural hippopotamoi) or hippos potamios
(plural hippoi potamioi). Since only the Latinized form in -us is found in English,
neither of these Greek plurals is needed. The shortened form hippo is
found only in English and can only take the plural hippos. You may sometimes
see hippoi used in English as the plural of hippo. Hippoi is properly the Greek
plural of hippos (”horse”), not of hippo.
Note that rhinoceros is a pachyderm of a different color. Both words are ultimately
from Greek, and the last syllable is pronounced the same in English,
but rhinoceri is not proper Latin (nor Greek). That form has found its way into
some English dictionaries, but I would advise against messing with rhinoceri. In
Latin rhinoceros is a third declension noun with the plural rhinocerotes. Rarely
you see the plural form rhinocerontes in English, but that is properly the plural
of a variant Latin singular form, rhinoceron. You’ll be laughed straight out of
the zoo if you try to use either one in English. Stick to rhinoceroses. Or better
yet, rhinos (certainly not rhinoi).
One other group of Latin nouns in -us is different. These are fourth-declension
masculine nouns. The plural in Latin is spelled the same as the singular, but
the u is pronounced long rather than short. When these words are borrowed
into English, the English-style plural is almost always preferred over the Latin.
We have censuses, hiatuses, sinuses, and fetuses (or foetuses). The seconddeclension
style endings are never correct, so no cenci, hiati, sini, or feti please.
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Apparatus is rarely pluralized in English. When a plural is needed, either apparatus
or apparatuses is acceptable, but never apparati. It so happens that
penus, the near homophone of penis that I mentioned above, is a real word in
Latin but of the fourth declension, so the plural is penus, not peni. It means
”household stock,” something you would presumably want to stow along with
the family jewels.
Yet another group of Latin nouns in -us follow different rules. If you’re still
taking notes, these form another subset of the third declension. Typically in
these cases the singular does not include the full root. The plural of genus
is genera (not genuses and certainly not geni). In English the plural of opus
(meaning a creative work) is opera (or opuses). In Latin, opera was originally
the plural of opus, but in both Latin and English, opera can correctly be treated
as a singular. In English the plural of opera (the thing that ain’t over till the
fat lady sings) is operas. When opera is used as a singular in Latin (where it
meant more of less the same thing as opus), the correct plural is operae, but
this is rarely if ever used in English.
Octopus is another of these third declension nouns in Latin, borrowed from
Greek. The Latin plural is octopodes, which is acceptable in English, but octopuses
(or even octopus) seems more at home in English. The form octopi is
quite common in English, but it is pseudo-Latin. It is based on the mistaken
belief that octopus was a second-declension noun like fungus. It has made its
way into many English dictionaries, but I would not recommend getting tangled
up with octopi. It is true that many standard English words have entered the
language through mistakes (an apron from a napron, pea from pease, etc.), so
octopi may not be totally indefensible. But people who know Latin, admittedly
not a large group, will think less of you for using it.
There is one more common English -us word borrowed from Latin that doesn’t
follow any of the rules above: virus. To the Romans a virus was a dangerous or
disgusting substance, anything from snake venom to body odor. Ancient grammarians
couldn’t agree whether the word was a third-declension noun, a fourthdeclension
noun or in a class by itself, but the one thing they could agree on was
that it didn’t have a plural form. Ever. To the Romans, it was a mass noun, not
a count noun. That hasn’t stopped English writers from inventing pseudo-Latin
plural forms to cover the modern countable senses of the word. Viri is formed on
the false assumption that virus is a second-declension noun. (Viri in fact is the
plural of Latin vir, ”man”.) Virii is an even worse mistake. Only Latin nouns
that end in -ius form the plural with -ii. There are no really common English
plurals in -ii other than radii. That hasn’t stopped people from trying out such
atrocious forms as virii and penii. Virii would be the plural of virius, if such a
word existed in Latin. Other suggested plurals include virora, vira, virua, and
vire. For more on the debate, see
http://www.perl.com/language/misc/virus.
html. The one inescapable fact is that in classical Latin, there was no plural of
the word. In English, the only correct plural is viruses.
Some English -us nouns were borrowed from other parts of speech in Latin
or from other forms (cases) of the noun than the usual nominative. Most of us
don’t get boni or ride bi (but I’m not judgmental if you do). We get bonuses and
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ride buses. Bonus is not a noun in Latin but an adjective meaning ”good”; bus
is a shortened form of omnibus, which is already a Latin dative plural meaning
”for all.” A few English nouns in -us derive from Latin verbs, so they can’t be
pluralized like Latin nouns. Mandamus means ”we order” in Latin, and ignoramus
means ”we are ignorant.” We can issue mandamuses to ignoramuses, but
we can safely ignore mandami from ignorami. And of course not all nouns that
end in -us are Latin at all. Walruses may sun themselves on taluses, but you
will search tali for walri in vain.
Since we’ve come this far, we may as well deal with some other common Latin
plurals that have found their way into English.
First declension Latin singulars end in -a in the singular and in -ae in the plural.
Often the English and Latin style plurals are both acceptable. You have larvae
(or larvas) and amoebas (or amoebae). When speaking of female graduates, you
say alumnae (but not alumnas). Sometimes which form to use depends on the
context. Radios have antennas but insects, unless they’re trying to tune in a
Rimsky-Korsakov number on the wireless, have antennae. Sometimes the plural
form is more common in English than the singular. Minutia is the singular of
minutiae and alga is the singular of algae.
There are a few Latin words in -a that do not form the plural in -ae because
they are third declension nouns borrowed from Greek. The English style plural
is usually best. Traumas, dramas, and dogmas are preferred over traumata, dramata,
and dogmata, but stigmata is preferred over stigmas. You should never
accept enemata from strangers.
A subset of the second declension ends in -um in the singular and in -a in
the plural. In English -ums is sometimes preferred. Forums (or fora), gymnasiums
(or gymnasia), podiums (or podia), but bacteria (not bacteriums), phyla
(not phylums). Seers are mediums but radio and television are two media. Data
is the plural of datum in Latin and English. English also has the plural form
datums, but only in the cartographic sense (meaning a reference point). In English,
purists still rail against using data and media with a singular verb. These
are instances of usages that began as mistakes but are now so common that
they are arguably correct. Another example of the same evolution is agenda. In
Latin (and sometimes in English) it is the plural of agendum (meaning ”a thing
that needs to be done”) but is now almost invariably treated as a singular in
English (meaning ”a list or set of things that need to be done”), with the correct
English plural agendas. Plural forms that take a further pluralization (correctly
or incorrectly) are called ”double plurals.” Other examples include the incorrect
forms alumnis and bacterias and the correct operas. One caution–quorum is a
genitive plural pronoun in Latin. The English plural is quorums, never quora.
Latin words ending in -ies are usually the same in the singular and plural,
both in Latin and in English. Series, species, caries (as in dental caries) are
correct as singular and plural.
Latin singulars ending in -on are borrowings from Greek and usually end in -a in
the plural in Latin. Phenomena (or arguably phenomenons, as in ”singing phe-
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nomenons”), ganglia (or ganglions). Sometimes the English-style plural seems
more natural, as in automatons (but automata is acceptable). Criteria is now
sometimes used as a singular in English, but it started life as the plural of criterion.
Latin singulars in -x have plurals in -ces or -ges in Latin, but in English -
ixes is usually preferred. Dominatrixes (or dominatrices), indexes (or indices),
cervixes (or cervices). The bones of the fingers and toes are phalanges but infantry
formations are more often phalanxes.
There are several odd words whose plurals will not be obvious from the above
rules. One oddball is pubes (two syllables, meaning the pubic region or pubic
hair). It is the same in the singular and plural in Latin and English. The supposed
singular pubis is pseudo-Latin, except when it means the pubic bone (in
full, os pubis, ”bone of the pubes”). The plural of specimen in Latin is specimina,
but in English specimens. The plural of exemplar is exemplaria in Latin,
but exemplars is a better model for English.
Some words from Latin are more common in the plural, so the singular form
may not be obvious. Mores (as in folkways and mores) has the rare singular
form mos. Viscera (the internal organs) has the rare singular viscus. Insignia
and regalia are the plurals of insigne and regale in Latin, but these singulars
are rare in English. Paraphernalia is a plural in English and Latin. It has a
rare English singular, paraphernal. The Latin singular, not found in English,
is paraphernalis. Feces (or faeces) is plural in Latin with the singular fex (or
faex). It is usually treated as a singular in English. Stamina started life as the
plural of stamen (”thread”) but is now usually a singular in English, except
sometimes when referring to sexual anatomy (of the botanical kind). Flowers
may have many stamina, but Gennifer’s former lover has much stamina.
The name of our species, Homo sapiens (literally ”wise human”) is singular in
both Latin and English. The plural of the phrase in Latin–in the non-technical
sense of a wise human–would be homines sapientes, but there is never any call
to use a plural in English. There is only one species called Homo sapiens. Homo
sapien as the supposed singular of Homo sapiens is an abomination. I call this a
”double singular.” Kudo as the supposed singular of kudos is another example.
Borrowed directly from the Greek, kudos (”praise”) is already singular. The
questionable form congery formed from the Latin singular congeries is another
instance. Bicep, tricep, quadricep, and forcep are incorrectly formed from biceps,
triceps, quadriceps, and forceps, which are already singular.
Gladiolus has given rise to a double singular too. Gladiolus is a Latin singular
with the plural form gladioli. This is probably the best choice for the
plural in English, but gladioluses is also acceptable. The similarity of sound of
-as and -us in unaccented English syllables makes some people believe the word
is gladiolas, which they suppose is a plural with the singular form gladiola. This
double singular has made its way into some dictionaries, but the shortened glad
would be a happier choice.
Other than Latin words and Greek words mostly borrowed through Latin, few
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words have been borrowed into English complete with their foreign plurals. In
the case of many of the western Romance languages (such as French, Spanish,
and Portuguese), it’s usually hard to tell because in these languages plurals often
end in the letter s, as in English. Linguists believe this form of the plural
in western Romance languages is derived from the Latin forms -as, -os, and -es
(first, second, and third declension masculine and feminine accusative plurals,
used for direct objects) and not, as you might expect, from forms like -es (third
declension nominative plurals, used for subjects). The native English pluralizing
suffixes spelled -s and -es (but often pronounced with a /z/ sound) come
from the same ultimate source (one class of proto-Indo-European plural endings),
but by a very different route. It is largely a matter of chance that Old
English and Old French happened to retain the same plural endings, almost
to the exclusion of the many other plural endings in PIE. After the Norman
invasion, the introduction of French -s may have hastened the decline of other
plural endings in English, but the process was already underway. We still have
oxen and brethren (if we can tell them apart), but we no longer wear shoen and
live in housen.
Unlike French and Spanish, Italian gets its plurals from the Latin nominative
rather than the accusative. When borrowed into English, these give us such
words as graffiti, which is properly the plural of graffito, but which is now often
treated as a singular in English. A particularly interesting case is bandit. We
anglicized the Italian bandito to bandit in the singular but still sometimes use
the Italian plural banditti alongside the English form bandits. Cognoscenti is
the plural of the obsolete Italian cognoscente. Also from Italian we get many
food terms that are plurals in that language, but treated as singular in English:
spaghetti, broccoli, and zucchini.
Some Hebrew plurals such as seraphim and cherubim exist alongside the Englishstyle
plurals like seraphs and cherubs. From Arabic, we have jinn (or djinn) as
the plural of jinni (or djinni).
Other languages are not often honored by having their plurals accepted on
equal terms. For example, you would never say that this Staff Report is longer
than many Icelandic sgur; you would say that this Staff Report is longer than
many Icelandic sagas. And that, I think, is quite long enough.
