foghorn vs fogsignal

foghorn and fogsignal both are nouns.

Word	Noun	Adjective	Verb	Adverb
foghorn	Yes	No	No	No
fogsignal	Yes	No	No	No

As nouns, foghorn and fogsignal are synonyms defined as:

foghorn and fogsignal: a loud low warning signal that can be heard by fogbound ships

foghorn (noun)	fogsignal (noun)
a warning device consisting of a horn that generates a loud low tone	a loud low warning signal that can be heard by fogbound ships
a loud low warning signal that can be heard by fogbound ships