Synonymous with sausage party and sword fight, a wang hang involves the intentional (or unintentional) exclusion of women from an all-male event. May be used both as an exclamatory statement, as well as in a derogatory fashion.
"I can't wait for the camping trip - no girls allowed - it will be a total wang hang!"
"I don't see any chicks at this party - yikes, this is a total wang hang - I'm out!"