(1) The hidden underlying reference to squareness, and boat-like shape, of the heads on Singaporeans (originally designed by the Merry Boat Heads clan as a way to insult without having to face the penalties/risks of being "offensive").

(2) It also can be referenced to the greatest gaming clan in Singapore - the notorious Merry Boat Heads.

Being insulted as a boathead is probably the worst thing you can imagine - yet each member of the Merry Boat Heads is, ironically, able to be compared to that of a God; they are each that amazing.

(3) It's a professional troll word - used by only the masters.
You're a boathead!
Don't worry; The Merry Boat-Heads crushed you - it's expected since the start!
Boathead!
by WCGPR0 February 27, 2012
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