1.
An STD.
Can be used to describe a large variety of sexually transmitted deseases but this term is most well known for meaning THE BIG ONE... HIV or AIDS.
"That girl is lucky she doesnt have the bug, after all that messing around she does"
Mental midget, someone who is a few beershort of a six pack, not the sharpest tool in the shed, a boatless booze cruise seeker, in short, someone who needs better meds
Now son, you see that naked man running naked down the street, screaming about headless chicken? He's a bug.....