Simple past tense and past participle of costume.(verb)
Wearing a costume; disguised.(adjective)
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Use "costumed" in a sentence
"In color books (or even in costumed hero books), you have other clues to tell you which character is which, but in B&W, the artist really needs to be able to have distinctive body shapes and facial features, or at least they do in the types of stories that Kleid is telling."
"Each of the four banners feature one of the main costumed characters from the film (from behind), and use the characters secret-identity name (Damon Macready as Big Daddy, not Nicholas Cage as …)."
"While I like my costumed heroes..."costumed" I will admit to thinking they hit upon the lack of them in the first X-Men movie with a fairly clever line: "What would you prefer, yellow spandex?""