Plural Nouns

In general, a noun is a person, place, or thing. A proper noun is a specialized name for a specific person, place, or thing. Proper nouns are always capitalized (e.g., “Crayola”). Nouns can be singular (i.e., only one) or plural (i.e., more than one).

To make a noun plural, add “s” (e.g., “dogs” is the plural form of “dog”), “es” (e.g., “boxes” is the plural form of “box”; add “es” to most nouns that end in “ch,” “s,” “sh,” “x,” and “z” to make them plural), and sometimes “ies” (e.g., “babies” is the plural form of “baby”; see the Notes section for exceptions to this grammar guideline) to the end of the noun.

Irregular plural nouns, which include terms like “women,” “men,” “children,” “alumni,” “feet,” “mice,” “data,” and so forth, usually are not made plural by adding “s,” “es,” or “ies” to their endings. However, some irregular plural nouns have the same endings as regular plural nouns, such as “leaves,” “knives,” “analyses,” and “theses.”

Usually, a surname is made plural by adding an “s” to the end of it (e.g., “Ayubis” is the plural form of the surname “Ayubi”), but there are exceptions. Add “es” to most surnames that end in “ch,” “s,” “sh,” “x,” and “z” to make them plural: for example, “Burch” becomes “Burches,” “Jones” becomes “Joneses,” “Nash” becomes “Nashes,” “Knox” becomes “Knoxes,” and “Hernández” becomes “Hernándezes.”  

However, if the “ch” at the end of a surname is pronounced with a hard “k,” like “Bach,” add “s” to the end of the surname to make it plural: “Bachs” (the same is true for common nouns ending in a hard “ch”: “stomachs”). Likewise, if the “x” at the end of a surname is silent, like “Rioux,” make the surname plural by adding an “s” to the end of the name: “Riouxs.”

Although there are many unique ways to form plural nouns, please note that placing an apostrophe “s” or just an apostrophe after an “s” at the end of a noun is not one of them. “Tuesday’s” and “cat’s” are never the plurals of “Tuesday” and “cat”; the plurals are “Tuesdays” and “cats.” In general, an apostrophe “s” is used to form the possessive case of a noun.

The spelling guidelines on this page serve as general pluralization recommendations and are not comprehensive. They are not specific to APA Style and can be found in many dictionaries and other style guides. The APA Style Experts frequently consult the Merriam-Webster.com Dictionary for their spelling guidance.

Some common examples of nouns in their singular and plural forms are presented next.

^a “Attornies” is not the plural form of “attorney” because the letter that precedes the “y” is a vowelopens in new window (i.e., an “e”) and not a consonantopens in new window. In general, do not change nouns that end in “y” to “ies” to make them plural if the letter that precedes the “y” is a vowel; add an “s” to the end of the noun to make it plural.

^b “Families” ends in “ies” because the letter that precedes the “y” in “family” is a consonant (i.e., an “l”). However, there are exceptions to this guidance. For example, “moneys” and “monies” are acceptable plural forms of “money.” When a term has more than one plural form, use your best judgment to determine which spelling is more appropriate to use in your work.

^c The term “persons” is sometimes used in research settings to refer to groups of a specific number and in a legal context such as “missing persons” or “persons of interest.” Nevertheless, “people” is the preferred plural form of “person.”

^d “Peoples” may be used to describe specific ethnic communities such as “Indigenous Peoples” or “First Peoples.”