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1.
Originated from the brand 'Lacoste',Costie is a word to define the steriotypical chracteristics of teenage boys.

'Look at that fit costie'
'He's such a costie'
Costie boys are typically boys with polo shirts, hoodies, cardians, medium build, slim fitting jeans, plimsoles, converse- (always white). Wears brands like All Saints, Topman, River Island
Likes bands like; Arctic Monkeys, Bloc Party.
by harrrrrrrrvanna November 13, 2009