1920's, Apple sauce, nonsense, or anything that is no good.
The new jazz band on WNAX is blaah.
by Bob Proczko October 16, 2006
1 more definition
a word sound used when in terms of ect. Also just cool to use any time.
u kno the guy who likes that girl and runs round, and owns a nice car and blaah
by Dave May 31, 2003