Merriam-Webster Collegiate Dictionary - jargon

 I. noun  Etymology: Middle English, from Anglo-French jargun, gargon  Date: 14th century  1.  a. confused unintelligible language  b. a strange, outlandish, or barbarous language or dialect  c. a hybrid language or dialect simplified in vocabulary and grammar and used for communication between peoples of different speech  2. the technical terminology or characteristic idiom of a special activity or group  3. obscure and often pretentious language marked by circumlocutions and long words  • ~y adjective  II. intransitive verb  Date: 14th century  1. twitter, warble  2. ~ize