v. trolled, trollĀ·ing, trolls
v.tr.
1.
a. To fish for by trailing a baited line from behind a slowly moving boat.
b. To fish in by trailing a baited line: troll the lake for bass.
c. To trail (a baited line) in fishing.
2. Slang To patrol (an area) in search for someone or something: "[Criminals] troll bus stations for young runaways" Pete Axthelm.
3. Music
a. To sing in succession the parts of (a round, for example).
b. To sing heartily: troll a carol.
4. To roll or revolve.
v.intr.
1. To fish by trailing a line, as from a moving boat.
2.
a. To wander about; ramble.
b. Slang To patrol an area in search for someone or something.
3. Music To sing heartily or gaily.
4. To roll or spin around.
n.
1.
a. The act of trolling for fish.
b. A lure, such as a spoon or spinner, that is used for trolling.
2. Music A vocal composition in successive parts; a round.
in chat rooms such as this, "trolling" is generally a term for starting a thread in order to promote (surreptiously, if sucessful) one's products/preferences/self, i.e. attempting to lure by stealth little fishies to your bait.