Pronunciation

change
  • (UK) (noun) (verb) IPA (key): /ˈkɒs.tjuːm/ or /ˈkɒs.tʃuːm/
  • (US) (noun) IPA (key): /ˈkɑs.t(j)uːm/ or /ˈkɑs.tʃuːm/ or /ˈkɑs.təm/
  • (US) (verb) IPA (key): /kɑsˈt(j)uːm/ or /kɑsˈtʃuːm/ or /ˈkɑs.t(j)uːm/ or /ˈkɑs.tʃuːm/
  • (file)

Singular
costume

Plural
costumes

 
Two men in costumes.
 
A woman in a costume.
  1. (countable) A costume is the clothes you wear that makes you look like someone or something else.
    For Halloween this year I wore a skeleton costume.

Plain form
costume

Third-person singular
costumes

Past tense
costumed

Past participle
costumed

Present participle
costuming

  1. If you costume yourself, you dress up with a costume.