Shel·ta (shěl'tə) n. A secret jargon used by traditionally itinerant people in Great Britain and Ireland, based on systematic inversion or alteration of the initial consonants of Gaelic words. Also called Cant, Gammon.
[From Shelta Sheldrū, perhaps alteration of Irish Gaelic béarla, language, English, from Old Irish bélrae, language, from bél, mouth.]