1. troll (a giant supernatural being, especially a grotesque humanoid creature living in caves or hills or under bridges) (originally Scandinavian mythology, now also European folklore and fantasy)

2. troll (a person who makes or posts inflammatory or insincere statements in an attempt to lure others into combative argument for purposes of personal entertainment or to manipulate their perception, especially in an online community or discussion) (by extension, originally Internet slang)