Yes

A costume designer designs costumes for theater, tv, film etc

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a costume designer is someone who desgins the costumes.

For example: I made the costume

Jan Musgrove has written:

'Make-up, hair and costume for film and television' -- subject(s): Costume, Film makeup, Television makeup

In the biopic Gandhi co-produced by NFDC, & directed by Richard Attenborough, the costume-designer was Bhanu Atthaiya from India, she also is the 1st Indian to win the Oscar for this film in 1982.

The film's Costume Designer was Louise Page, and Michael Weldon was the Assistant Costume Designer.