elapid snake vs serpent

elapid snake and serpent both are nouns.

Word	Noun	Adjective	Verb	Adverb
elapid snake	Yes	No	No	No
serpent	Yes	No	No	No

As nouns, serpent is a hypernym of elapid snake; that is, serpent is a word with a broader meaning than elapid snake:

elapid snake: any of numerous venomous fanged snakes of warmer parts of both hemispheres
serpent: limbless scaly elongate reptile; some are venomous

Other hypernyms of elapid snake include ophidian, snake.

elapid snake (noun)	serpent (noun)
any of numerous venomous fanged snakes of warmer parts of both hemispheres	limbless scaly elongate reptile; some are venomous
	an obsolete bass cornet; resembles a snake
	a firework that moves in serpentine manner when ignited