Someone who achieves a feat of skill through nothing but luck
You landed that 3-pointer?! What a tin ass!
by tin ass September 10, 2003
1 more definition
Do have been shagged by so many sheep that your behind begins to take on a dark shade of grey resembling tin.
Man: That tokoroan lad is a bit of a tin ass.
by Tui_Pure3 July 16, 2011