Webster's Revised Unabridged Dictionary · 1913

Costume

Costume (k?s"t?m` o k?s-t?m") , noun

[French costume, Italian costume custom, dress, from Latin consuetumen (not found), for consuetudo custom. See Custom, and compare Consuetude.]

1.
Dress in general; esp., the distinctive style of dress of a people, class, or period.
2.
Such an arrangement of accessories, as in a picture, statue, poem, or play, as is appropriate to the time, place, or other circumstances represented or described.
I began last night to read Walter Scott's Lay of the Last Minstrel....I was extremely delighted with the poetical beauty of some parts....The costume, too, is admirable. — Sir J. Mackintosh
3.
A character dress, used at fancy balls or for dramatic purposes.