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http://isp.webopedia.com/TERM/T/troll.html

troll


(v.) (1) To deliberately post derogatory or inflammatory comments to a community forum, chat room, newsgroup and/or a blog in order to bait other users into responding.

(2) To surf the Internet.

(3) To hang around a chat room reading the posts instead of contributing to the chat.

(n.) One who performs any of the above actions.