Green’s Dictionary of Slang

1. to commit oneself wholeheartedly.

1890		Sporting Times 29 Mar. 1/1: From this we infer that the ‘old ’un’ means to go for it tooth and nail.
1902		Bulletin (Sydney) 30 Aug. 15/4: The driver was having a look around his engine to see that all was ready to ‘go for it’ as soon as he could get away.
1944		News of the World 11 June 6: Women will go for it one hundred per cent.
1976		Jenkins & Shrake Limo 148: ‘Surfing’s an art form. Surfing’s where you just get it together, man [...] You’re goin’ for it’.
1979		Lette & Carey Puberty Blues 15: We were all going for it up the back of the hall.
1992		R.G. Barrett White Shoes 21: But Les didn’t ‘go for it’ as KK told him. He would have liked to; it would have been something else to put his foot down.
2000		N. Griffiths Grits 230: Christ ya wir fuckin gowin for it last night, wirnt ya?
2013		C. Dundas ‘Rightful King of Wrestling’ in ThugLit Nov.-Dec. [ebook] I told him fuck it, go for it.

2. of a woman, to be sexually enthusiastic.

1969		‘Iceberg Slim’ Pimp 28: I was frantic to sock ‘it’ into every young girl weak enough to go for it.
1999		Indep. on Sun. Real Life 5 Sept. 2: I looked up and saw her really going for it with a gang of lads.

3. to make an effort, to overcome one’s fears, to get on energetically.

1977		Eble Campus Sl. Apr. 2: go for it – to carry on an action.
1988		D. Woodrell Muscle for the Wing 221: I think you’re gonna go for it, Shug.
1993		I. Welsh Trainspotting 65: Let’s go for it cats, let’s get it on.
2001		J. Stahl Plainclothes Naked (2002) 262: You wanna go for it, I’m giving you a way to improve your situation.

4. (US campus) to seduce.

1976

Eble Campus Sl. Nov. 3: go for it – to attempt to pick up someone of the opposite sex.