A verbal conversation taking place between 2 or more heterosexual men. Normally taking place prior to a time of slumber. ANY topic can be spoken about between members of the group. The contents of a mansation may not be brought up to other individuals that did not participate in the mansation.
Sam, Jory, and Nolan had a mansation for the record books last night.

or

Jory: What did you think about the vag we were talking about in our mansation last night?
Sam: That shit was epic.

Nolan: Wait what vag were you talking about?
Jory: Don't worry about it.
by midnightexpress October 21, 2009
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