look up any word, like cunt:
 
1.
An "Old Australian" word; an derrogatory term that means a "loud-mouthed idiot." Named specifically for the galah, a native Australian bird that makes a distinctive (and quite funny-sounding) call.
"Oh, Scotty, ya bloody galah! What are you ON ABOUT?!"
by beano June 29, 2003
 
2.
A real fool. Often a fool that spends their time jabbering.
by drl May 22, 2003
 
3.
A cider-fuelled idiot with a propensity to chase plastic round muddy fields. High tendency towards gingervitis.
Look at that group of Galahs over there. You can almost smell the cider.
by Brit Abroad November 29, 2010