jargon

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Nonsensical, incoherent, or meaningless talk.
2. n. A hybrid language or dialect; a pidgin.
3. n. The specialized or technical language of a trade, profession, or similar group. See Synonyms at dialect.
4. n. Speech or writing having unusual or pretentious vocabulary, convoluted phrasing, and vague meaning.
5. v. To speak in or use jargon.

Century Dictionary and Cyclopedia

1. n. Confused, unintelligible talk; irregular, formless speech or language; gabble; gibberish; babble.
2. n. Specifically A barbarous mixed speech, without literary monuments; a rude language resulting from the mixture of two or more discordant languages, especially of a cultivated language with a barbarous one: as, the Chinook jargon; the jargon called Pidgin-English.
3. n. Any phraseology peculiar to a sect, profession, trade, art, or science; professional slang or cant.
4. n. Synonyms Chatter, Babble, etc. See prattle, n.
5. To utter unintelligible sounds.
6. n. A colorless, yellowish, or smoky variety of the mineral zircon from Ceylon. The gray varieties are sold in Ceylon as inferior diamonds, and called Matura diamonds, because most abundant in the district of Matura.

Wiktionary

1. n. A variety of zircon
2. n. uncountable A technical terminology unique to a particular subject.
3. n. countable Language characteristic of a particular group.
4. n. uncountable Speech or language that is incomprehensible or unintelligible; gibberish.

GNU Webster's 1913

1. n. Confused, unintelligible language; gibberish.
2. n. an artificial idiom or dialect; cant language; slang. an idiom with frequent use of informal technical terms, such as acronyms, used by specialists.
3. v. To utter jargon; to emit confused or unintelligible sounds; to talk unintelligibly, or in a harsh and noisy manner.
4. n. (Min.) A variety of zircon. See zircon.

WordNet 3.0

1. n. a colorless (or pale yellow or smoky) variety of zircon
2. n. specialized technical terminology characteristic of a particular subject
3. n. a characteristic language of a particular group (as among thieves)