A west coast prostitute with a very beaten vagina. Specifically, a very smelly vagina.
Can also be used as a verb when the person preforming the action is acting like a tuna rat.
Noun: Ewe! That whore has the nastiest tuna rat I have ever smelt!
Verb: Kristina was tuna rattin' real hard last night!
by Tyler, Matt, and Daniel February 22, 2009
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