1.NounOne who imitates or plagiarizes the work of others. .mw-parser-output .defdate{font-size:smaller}
2.NounA criminal who imitates the crimes of another; specifically, a criminal who commits the same crime, especially a highly-publicized one, that has recently been committed by someone else.
"a copycat strangler"
3.AdjectiveImitative; unoriginal.
"copycat crime"
4.VerbTo act as a copycat; to copy in a shameless or derivative way.