Definition from Wiktionary, the free dictionary
See also 
gimme (plural gimmes)
- (colloquial) something easily obtained
- It's a gimme.
- (golf) A tap-in putt, usually a couple inches from the cup.
- Don't count two strokes for that - it was a gimme, if I wasn't holding the flag with my other hand, for the next players waiting on the hole, it would have gone in.