1 a person who criticizes someone or something severely:
2 used in nouns meaning someone who hits or attacks a particular type of person:
3 used in nouns meaning someone who strongly criticizes a particular type of person or thing:
He thrives on an opponent's power but will never be anything more than a back-court basher.
She believes the police force protects brutal bashers and outright liars.
The chairman of the conference is a Christian basher.
I just read a good article about the scientific ignorance of today's science bashers.