Definition of "for it"

for it

prepositional phrase
1. In order to attain some implied goal.
  Quotations
  And then, tenebrously, his mind whispered: Do it anyway. Put her down and swim for it.But he did not, could not. An awful guilt rose in him at the thought.
  1982, Stephen King, The Raft
2. Facing punishment for a misdeed.
3. Corresponding in volume.
4. Used other than figuratively or idiomatically: see for,‎ it.