A man or women who are right handed but masturbate with their left hand watching pron on the Internet because the right hand is clicking on the mouse. Usually refers to someone who is somewhat homely.
Dude look at him, he's not getting laid anytime soon, he's definitely a leftander.
Found this great site, pull a leftander all night!
When an acquaintance travels a long distance to specifically visit you and you “forget” you have a work meeting 1000 miles away, subsequently forcing said acquaintance to stay with with remotely related foreign cousins in a shitty neighborhood.
I flew all the way from Singapore to visit my buddy Jason, but turns out he was Pulling a Lettmann and was in Boston when I arrived. Instead I was forced to stay in Oakland with my 1/8 cousin from a Vietnam who kept stroking my fro.