n. phr. , slang 1. A bad person; a person not liked. I don't like Charley; keep that son of a gun out of here.
Synonym: BAD ACTOR. 2. A mischievous rascal; a lively guy. Often used in a joking way. The farmer said he would catch the son of a gun who let the cows out of the barn. Hello Bill, you old son of a gun!
Compare: SO AND SO. 3. Something troublesome; a hard job. The test today was a son of a gun. Used as an exclamation, usually to show surprise or disappointment. Son of a gun! I lost my car keys.
Compare: SON OF A BITCH.