From The Collaborative International Dictionary of English v.0.48:
Nipper \Nip"per\, n. 1. One who, or that which, nips. [1913 Webster]
2. A fore tooth of a horse. The nippers are four in number. [1913 Webster]
3. A satirist. [Obs.] --Ascham. [1913 Webster]
4. A pickpocket; a young or petty thief. [Old Cant] [1913 Webster]
5. (Zool.) (a) The cunner. (b) A European crab (Polybius Henslowii). [1913 Webster]