1.) a way to express approval of something that someone just did, but only if your either retarted or a hillbilly or jus don't fuckin know whether the "do-gooder" is a dude or a lady
2.) also used as a sarcastic insult if someone fucks something up
phrase is similar to: good job young man or thatta girl
1.)*man helps elderly woman cross the street*
retarted hillbilly-"Thatta boy young lady!"
guy-"wtf is wrong with u, fuck off weirdo!"
retarted hillbilly-"thatta boy young lady !"
guy-"fuckin dumbass" *sighs and walks off*
2.)*girl slips on pencil and falls on her ass*
sarcastic asshole(me)-"Thatta boy young lady!"
girl-"fuck u ass hole!" *angry face*
me-"oops wrong time of the month" *walks away repeatedly looking back over shoulder*