make dirty

she didn't like him dirtying her nice clean towels

covered or marked with an unclean substance

a tray of dirty cups and saucers

her boots were dirty

(of an activity) dishonest; dishonourable

he had a reputation for dirty dealing

concerned with sex in a lewd or obscene way

he told a stream of dirty jokes

(in popular music) having a distorted or rasping tone

Nirvana's dirty guitar sound