One who sends pictures of his/her own genitalia to others via social media, most commonly over Twitter.
That tweiner sent pics of his junk that would make a fantastic ad for those little sausages people put out as holiday party treats
by Russ68 June 16, 2011
Noun - the slang name commonly given to Facebook upon the discovery that over half of the users are now age 35+
by Russ68 June 16, 2011