Originates from high five
A belly five is an action, where two or more people jump up against each other so as to bounce off each others' stomachs.
Is often done as a symbol of celebration.
Dude, I just bought a can of Coke for the classic price of 30p! Belly five!
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
Buy the mug