Belonging to or associated with Batman; sometimes said of bat-themed objects used by him.
2002 October 27, Richard B. Becker, “Re: The most implausible thing about BoP (no spoilers)”, in rec.arts.comics.dc.universe[1] (Usenet), message-ID <3DBCA45A.F8B8C1AF@mindspring.com>:
Holy unsafe sex, Batman! Did you forget to use your Bat-condom?