Pluralization

How to write about multiple things.

In English, words used to represent a person, place or thing (nouns) are modified when they're used to refer to multiple occurrences of the people, places or things. This subchapter describes the rules for specifying plurals.

Add an "s" to the End of a Noun to Make It Plural

In most cases, you add the letter "s" to the end of a noun to make it plural. For example:

Chair becomes chairs.
Umbrella becomes umbrellas.
Worm becomes worms.

Add an "es" to the End of a Noun That Ends in "s" to Make It Plural

When a noun ends in the letter "s", add "es" to the word to make it plural. For example:

Business becomes businesses.
Class becomes classes.

Replace the "y" with "ies" at the End of a Noun That Ends in "y" to Make It Plural

When a noun ends in the letter "y", replace the letter "y" with the letter string "ies" to make the noun plural. For example:

Sky becomes skies.
Bunny becomes bunnies.

Notable Exceptions to These Rules

There are many exceptions to these simple rules of pluralization. Here are some of the more notable ones:

Mouse becomes mice.
Goose becomes geese.
Iris becomes iris, not irises.
Buffalo becomes buffalo, not buffalos.

Note the last example in which the same word is used to express both singular and plural forms of the noun.

Scientific Writing and Latin Pluralization

English is rich with words from many languages. Primarily used in the scientific community, Latin has made major inroads into the English language. In Latin, pluralization is most often achieved by replacing the end of a word with the letter "i" as in this example:

Octopus becomes octopi.

Unfortunately, a detailed discussion of the rules for pluralization in Latin falls well beyond the scope of this introductory guide.