Green’s Dictionary of Slang

1. to bring to orgasm.

1977		(con. 1965) P. Caputo Rumor of War 157: ‘What I want to know is, did you get your socks blown off? Did one of those honey-wa’s blow your socks off?’.
1981		(con. 1966) P. Conroy Lords of Discipline 229: How many times did you say you blew her socks off?

2. see knock the socks off under knock v.