Plural of Rhinoceros

by Craig Shrives

The Quick Answer

The plural of rhinoceros is rhinoceros or rhinoceroses.

The Plural of Rhinoceros

The original and most common plural of rhinoceros is rhinoceros, but rhinoceroses, which adheres to the standard rules for forming plurals in English, is also commonly used.
  • Weighing around 600kg, Sumatran rhinoceros are the smallest. White rhinoceros are the largest, weighing up to 3,500kg. correct tick
  • (Rhinoceros is the most common plural.)
  • Male rhinoceroses are called "bulls" and female rhinoceroses are called "cows." Their young are "calves." correct tick
  • (Rhinoceroses is an acceptable alternative.)
plural of rhinoceros

What about "Rhinoceri"?

The noun rhinoceros has a Greek root. More specifically, it comes from the Greek word rhinokeros (nose-horned), which is an amalgam of rhis (nose) and keras (horn). As rhinoceros derives from Greek, there is no justification for the plural rhinoceri, which would be a Latin-style plural.

What about "Rhinocerotes"?

In recognition of its Greek root, some academics opt for the plural rhinocerotes, but, put simply, this is not an English word. It is not the English plural of rhinoceros.

What about "Rhino"?

The word rhino is a common alternative for rhinoceros. With rhino, there is no debate. The plural is rhinos. If your text is informal enough to use rhinos, go for it. Easy life.

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The Standard Rules for Forming the Plurals

The table below shows the standard rules for forming the plurals of nouns in English.
Type Example of Type Forming the Plural Plural
Most Nouns lamp
add s lamps
Noun Ending s, sh, ch, x or z rhinoceros
add es rhinoceroses
Nouns ending [consonant] o hero
add either s or es
(There are no rules for this - you have to know.)
Nouns ending [vowel] o patio
add s patios
Nouns ending [consonant] y story
change the y to an i and add es stories
Nouns ending [vowel] y donkey
add s donkeys
Nouns ending f or fe dwarf
ves and/or s
(There are no rules - you have to know.)
hooves or hoofs
Exceptions man
some nouns undergo a vowel or letters change men
More exceptions salmon
some nouns do not change at all salmon
Foreign rulings radius
some nouns adopt foreign rulings radii
Read more about English spelling rules.

Why Is There Confusion over the Plural of Rhinoceros?

Confusion arises over the plural of rhinoceros because the erroneously assigned Latin plural rhinoceri grew in popularity, most probably because it sounds funny and clever. The original plural of rhinoceros was simply rhinoceros (i.e., no change), but native English speakers are more drawn to rhinoceroses, which adheres to the standard ruling for forming plurals.

Rhinoceros is more common than rhinoceroses. [evidence]

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