From Wiktionary, the free dictionary
From pain + play.
painplay (uncountable)
- (BDSM) Any sexual practice involving the intentional infliction of pain.
1996 December 17, k'Shandra, “Reflections on Safewording (long)”, in alt.sex.bondage[1] (Usenet):I do not have much experience with painplay, and am not sure how much I'll be able to take, but I'm prepared to find out.
2000 December 24, Sockermom9 [username], “Re: Psycology of BDSM”, in soc.subculture.bondage-bdsm[2] (Usenet):I was originally into plain old bondage, but have found that both submission and painplay are things that I can eroticize.
2002 June 24, Janet Hardy, “Re: sub vs bottom”, in soc.subculture.bondage-bdsm[3] (Usenet):But I'm curious -- what got you started doing BDSM? What fantasies were intense enough to drive you to try painplay in the first place?