The city of Melbourne has a cultural festival using the Aboriginal word Moomba. It seems the festival's initial organisers asked the local Aborigines to suggest a name, and were told that moomba means 'lets get together and have fun.' The grateful organisers subsequently used the name.
In hindsight, the organisers really should have been suspicious that 'lets get together and have fun' could be expressed in two syllables. In reality, 'moom' means 'bum', 'buttocks', or 'anus', while the suffix 'ba' means 'in', 'at' or 'on'. So moomba actually means 'in the bum.'
Larry: That girl is hot!
Dave: No chance, I moomba-ed her last night
A bruise usually on a girls thigh, that is put there, from having sex to hard.
What the **** Johnny, I got another Moomba from you pushing so hard!