jargon vs rhyming slang

jargon and rhyming slang both are nouns.

Word	Noun	Adjective	Verb	Adverb
jargon	Yes	No	No	No
rhyming slang	Yes	No	No	No

As nouns, rhyming slang is a hyponym of jargon; that is, rhyming slang is a word with a more specific, narrower meaning than jargon:

jargon: a characteristic language of a particular group (as among thieves)
rhyming slang: slang that replaces words with rhyming words or expressions and then typically omits the rhyming component

Other hyponyms of jargon include street name.

jargon (noun)	rhyming slang (noun)
a characteristic language of a particular group (as among thieves)	slang that replaces words with rhyming words or expressions and then typically omits the rhyming component
specialized technical terminology characteristic of a particular subject
a colorless (or pale yellow or smoky) variety of zircon