a bad egg

a bad egg

A dishonest or ill-behaved person. Primarily heard in US. We could tell he was a bad egg even at a young age.
See also: bad, egg

a bad egg

  (mainly American informal)
someone who behaves in a bad or dishonest way He's a bad egg - don't believe anything he says.
See also: bad, egg
References in classic literature ?
I observed the doctor sniffing and sniffing, like someone tasting a bad egg.
Whin a bad egg is shut av the Army, he sings the Divil's Mass for a good riddance; an' that manes swearin' at ivrything from the Commandher-in-Chief down to the Room-Corp'ril, such as you niver in your days heard.