1. Slang for a big or exciting party: The family threw Latoya a birthday bash which was just one of several bashes they have thrown for her.
2. Powerful and hard blows: Shelia used a hammer to give a resounding bash or two on the coconut shell in order to break it apart.

1. To strike with a heavy, crushing blow: The gang member bashed the hood of the car with a sledgehammer.

The two cars bashed into each other.

2. To beat or to assault severely: The police arrested the men who bashed and robbed a man who was walking in his neighborhood last evening.
3. To make comments that find fault in someone or to criticize and to disparage something or another person or group: The talk-show-host was bashing a political group with hate mongering and vulgar talk on his program one night.