And here is the Encyclopaedia Britannica reference for the actual term, in the actual field of linguistics:
in colonial history, an unstable rudimentary hybrid language used as a means of communication between persons having no other language in common. Although the term was long synonymous with pidgin—as can be seen by the use of jargon in the names of such pidgins as Chinook Jargon and Mobilian Jargon—in the 1980s some linguists began restricting its use to denote pre-pidgins, or early developmental forms of pidgins.
Nonlinguists more commonly define jargon as the technical or specialized parlance of a specific social or occupational group such as physicians or lawyers. Jargon has also historically been defined as gibberish or as an outlandish, unintelligible, barbarous, debased language; in this meaning it is similar to patois and carries negative connotations. When the term jargon was originally applied to pidgins, it no doubt reflected the negative attitudes toward pidgins held by fluent speakers of the languages from which the pidgins derived most of their vocabularies. Indeed, jargons and pidgins were often characterized as “broken” languages, suggesting that they lack grammar, in contrast to full-fledged languages that function as the vernaculars of particular communities. Technically, jargons and pidgins have no native speakers and are used only as lingua francas, although expanded pidgins may be used as vernaculars.
Anyhow, you're right, we should leave well enough alone.