adjective
BAD : Every year we make new uniforms for the carnival.
GOOD : Every year we make new costumes for the carnival.
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uniform = a set of clothes worn by soldiers, police officers, nurses etc when on duty, and children in some schools: 'Some children hate having to wear their school uniform.'
costume = a set of clothes worn by actors or public performers: 'She used to work for a theatre company, designing and making costumes.' 'The tourist guides at the castle all wear medieval costumes.'