noun

1. One who bashes something, figuratively or literally.

2. One who engages in gratuitous physical or verbal attacks on a group or type of people.

   "He was beaten up by a queer-basher."

3. A trainspotter. http//groups.google.co.uk/groups/search?q=%22bashers%22+uk+railway&btnG=Search&sitesearch=groups.google.com

4. A rainproof sheet for sleeping under.