bad-boy

Noun

bad boy (plural bad boys)

1. A man whose rebellious nature makes him dangerous or attractive.
   • Yeah, I fit the profile all right. Perfect made-to-order malcontent. Let's sign this bad boy up and sic him on somebody fast, before the foam dries on his mouth.2012, Douglas MacKinnon, Vengeance Is Mine, →ISBN
2. (slang) A male criminal.
3. (figuratively, slang) An undesirable or difficult task.
   • Let's get this bad boy done!
4. (slang) A powerful or impressive product or item.
   • Many school music teachers and directors are not primarily clarinetists and, knowing little of the subtle intricacies of this "bad boy" of instruments, can teach little more than the fingering.1949 November-December, Floyd E. Low, “Keep that pitch UP!”, in The Instrumentalist, volume 4, Association for the Advancement of Instrumental Music, page 38

   Synonyms:

   bad baby

5. Used other than figuratively or idiomatically: see bad, boy.