waa Share definition Flag 1. Bullshit! That's a lie. 2. Reverses the meaning of a statement. Variation is wah! See similar meaning wordis it/word 1. Baz: "I have a huge dick" Jay: "Waa". 2. Jay to Baz: "Your penis is big, waa!" waa by X-treem August 28, 2003 Get the waa mug.