Green’s Dictionary of Slang

1. (US, also stag it) of a man, to attend a social function without a female companion.

1900		E.H. Babbitt ‘College Words and Phrases’ in DN II:i 64: stag, v. In phrase ‘to stag it,’ to go to a party without escorting a lady.
1915		Daily Trib. (Bismarck, ND) 21 Apr. 11/1: When a good show comes to town Oh you vanishing kid! He stags it or ‘has to work tonight’.
1920		F.S. Fitzgerald This Side of Paradise in Bodley Head Scott Fitzgerald III (1960) 129: He had particularly wanted to stag that game and entertain some Harvard friends.
1941		‘Digg Mee’ ‘Observation Post’ in N.Y. Age 18 Oct. 9/7: Robt. Morton, D. Brown and Horace Dickerson ‘stagging it’.
1962		(con. 1940s) H. Simmons Man Walking On Eggshells 161: The guys came down to see, some stagging, some dragging their chicks along.

2. to be a bachelor.

1928

C. McKay Home to Harlem 204: Young men who were stagging through life, passing along with brown-paper packages, containing a small steak, a pork chop, to do their own frying.

3. (US campus) to reject a request for a date; thus stagged adj., rejected.

1967–8

Baker et al. CUSS 203: Stagged Turned down when asking for a date.