syph vs neurosyphilis

syph and neurosyphilis both are nouns.

Word	Noun	Adjective	Verb	Adverb
syph	Yes	No	No	No
neurosyphilis	Yes	No	No	No

As nouns, neurosyphilis is a hyponym of syph; that is, neurosyphilis is a word with a more specific, narrower meaning than syph:

syph: a common venereal disease caused by the treponema pallidum spirochete; symptoms change through progressive stages; can be congenital (transmitted through the placenta)
neurosyphilis: syphilis of the central nervous system

Other hyponyms of syph include primary syphilis, secondary syphilis, tertiary syphilis.

syph (noun)	neurosyphilis (noun)
a common venereal disease caused by the treponema pallidum spirochete; symptoms change through progressive stages; can be congenital (transmitted through the placenta)	syphilis of the central nervous system