jargon vs drop-dead

jargon is a noun but drop-dead is not a noun.

Word	Noun	Adjective	Verb	Adverb
jargon	Yes	No	No	No
drop-dead	No	No	No	Yes

jargon (noun)	drop-dead (noun)
a characteristic language of a particular group (as among thieves)
specialized technical terminology characteristic of a particular subject
a colorless (or pale yellow or smoky) variety of zircon

jargon (adverb)	drop-dead (adverb)
	stunningly or breathtakingly