1> Donegal slang for something so complex it is only to be reffered to a goats knee, pressumibly because they are quite hard.

OR

2> Used as a phrase to describe something/someone or how they make you feel.
1:- Jeekers boys, that Hendrix riff is Harder than a goats knee!

2:- Jaime: Jesus Richard, your sister gets me

*Pétur and Jaime in unison*

HARDER THAN A GOATS KNEE. AHAHAHAHAHAHAHAH AHAHA AHA No put seriously, we've spit roasted her.
by Jaime-the-ledge January 18, 2010
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