Plural of Rhinoceros

What Is the Plural of Rhinoceros?

The Quick Answer

The plural of "rhinoceros" is "rhinoceros" or "rhinoceroses."

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.
Male rhinoceroses are called "bulls" and female rhinoceroses are called "cows." Their young are "calves."

Table of Contents

Are You Good at Plurals?
The Standard Rules for Forming the Plurals
Why Is There Confusion over the Plural of Rhinoceros?
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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 scythe	add s	lamps scythes
Noun Ending s, sh, ch, x or z	rhinoceros dress	add es	rhinoceroses dresses
Nouns ending [consonant] o	hero zero tomato	add either s or es (There are no rules for this - you have to know.)	heroes zeros tomatoes
Nouns ending [vowel] o	patio ratio	add s	patios ratios
Nouns ending [consonant] y	story penny	change the y to an i and add es	stories pennies
Nouns ending [vowel] y	donkey chimney	add s	donkeys chimneys
Nouns ending f or fe	dwarf hoof	ves and/or s (There are no rules - you have to know.)	dwarfs hooves or hoofs
Exceptions	man louse	some nouns undergo a vowel or letters change	men lice
More exceptions	salmon sheep rhinoceros	some nouns do not change at all	salmon sheep rhinoceros
Foreign rulings	radius medium	some nouns adopt foreign rulings	radii media

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]