Other than the superhero himself, 'batman' is used as a term to describe something cheesy and usually old school, but still cool - something that is 'camp'. (i.e. listening to certain 90's music, watching certain old television shows, etc.)

When a male paints his scrodum black with Paint or Ink and receives oral sex (from male or female). The giver of the oral sex is lying on the bed with his or her head hanging off the edge of the bed. While giving oral sex, the male scrodum is tapping against the givers eyes and nose area shading this area of the face black thus revieling a look that resembles a BatMan Mask.

Worlds greatest dectevive

a term for someone who would use their parents ashes as lube, if given the chance

A superhero created by Bob Kane who orginally appeared in DC comics and then evolved onto tv and cinema screens.

Musical term, adapted from traditional Italian "batmani"

Denotes a section with a heavy, repeated 2 note rhythm. The most famous example in popular music is the Theme from Batman

Guitarist: Take it from the third chorus
Bassist: ..Duh...
Guitarist: <sigh> The batmans.
Bassist: OK. D D____ D D ____D D _____D D_____

A sexual act where mid copulation you kill your partners parents, preferably by shooting them.