fingerboard vs signpost

fingerboard and signpost both are nouns.

Word	Noun	Adjective	Verb	Adverb
fingerboard	Yes	No	No	No
signpost	Yes	No	Yes	No

As nouns, signpost is a hypernym of fingerboard; that is, signpost is a word with a broader meaning than fingerboard:

Other hypernyms of fingerboard include guidepost.

fingerboard (noun)	signpost (noun)
a narrow strip of wood on the neck of some stringed instruments (violin or cello or guitar etc) where the strings are held against the wood with the fingers	a post bearing a sign that gives directions or shows the way
a bank of keys on a musical instrument
a guidepost resembling a hand with a pointing index finger

fingerboard (verb)	signpost (verb)
	mark with a signpost, as of a path