It is the behavior of keeping
something a secret
in confidence. Often used as an adjective to describe information
being exchanged that is to be held
The term orginates from the idea that once something has entered a black
hole, it cannot
The "w" is silent.
Al: So you let her in your office? What did she want?
Bill: Yeah, I did-- and this is blackwholism, ok?
Al: Of course!
Bill: She wanted
me to use a CIGAR!
Al: WHAT?! At least it's biodegradable.