Irregular Plurals

There are two types of irregular plurals:

  1. Words that don't change.
  2. Words that don't follow plural spelling rules.

Words That Don't Change

These words are the same in the singular and plural form.

Words With the Same Singular and Plural Forms
Singular (1) Plural (2+)
aircraft aircraft
deer deer
fish fish
moose moose
offspring offspring
sheep sheep
species species
salmon salmon
trout trout

Many of these words refer to animals. A lot of fish names also follow this pattern.

Words That Don't Follow Plural Spelling Rules

Irregular Plurals
Singular (1) Plural (2+)
child children
die dice
foot feet
goose geese
louse lice
man men
mouse mice
ox oxen
person people
tooth teeth
woman women

Many compound words that end with an irregular plural follow the same pattern.

Irregular Plurals
Singular (1) Plural (2+)
workman workmen
schoolchild Schoolchildren

Learn the spelling rules for regular plurals.

Learn more about using plurals.