goatsucker vs nightjar

goatsucker and nightjar both are nouns.

Word	Noun	Adjective	Verb	Adverb
goatsucker	Yes	No	No	No
nightjar	Yes	No	No	No

As nouns, goatsucker and nightjar are synonyms defined as:

goatsucker and nightjar: mainly crepuscular or nocturnal nonpasserine birds with mottled greyish-brown plumage and large eyes; feed on insects

Other synonyms of goatsucker include caprimulgid.

goatsucker (noun)	nightjar (noun)
mainly crepuscular or nocturnal nonpasserine birds with mottled greyish-brown plumage and large eyes; feed on insects	mainly crepuscular or nocturnal nonpasserine birds with mottled greyish-brown plumage and large eyes; feed on insects