look up any word, like sparkle pony:
 
1.
The last name of a crazy irish family.
Those Hallahans sure know how to party.
by happydayandnight March 05, 2010
 
2.
Where a chick fucks you in the ass with a strap-on; but its not gay.
"Dude, my girlfriend gave me a HALLAHAN last night. But it was a girl so it wasn't gay.
by ShaineSixxSeven April 08, 2011
 
3.
Someone You Generally Can't Stand Maybe It's Their Face, Personality, Social Skills Or Lack Of Intelligence; You Try Your Absolute Hardest To Get Away But Always Resulting In Failure.

Example:
Person 1: Shit Me It's The Hallahan, Hide.
... 1 Minute Later...
The Hallahan: Hey Guys, Ooo I Love Hide And Seek!
by Wag1Brother July 24, 2009
 
4.
The act if taking a strap-on up the ass by a girl and thinking that its not gay
The man asked the hooker to give him a hallahan
by Deathwish1659 April 15, 2011