1 definition by sup my lo

The act of completing a task with no forethought or planning what so ever.

Normally in one tenth of the time it should take to do.
Person 1: "I need a nuclear power station safety system for tomorrow".

Person 2: "No problem, i'll 'whack it in' this afternoon".
by sup my lo November 25, 2004
Get the whack it in mug.