1) A mistress or a "bit on the side".

2) Someone willng to accept a booty call.
Boris: Who's that then Scotsman?

Scotsman: She's my gash on a lash.

Boris: That's disguating Scotsman.
by scotsman_too_hotsman March 7, 2009
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A group of soemwhat promiscuous young ladies going out on the town and getting drunk, usually behaving badly.
Here comes some more gash on the lash!
by Ace w-n February 27, 2008
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