woodpecker vs piciform bird

woodpecker and piciform bird both are nouns.

Word	Noun	Adjective	Verb	Adverb
woodpecker	Yes	No	No	No
piciform bird	Yes	No	No	No

As nouns, piciform bird is a hypernym of woodpecker; that is, piciform bird is a word with a broader meaning than woodpecker:

woodpecker: bird with strong claws and a stiff tail adapted for climbing and a hard chisel-like bill for boring into wood for insects
piciform bird: any of numerous nonpasserine insectivorous climbing birds usually having strong bills for boring wood

woodpecker (noun)	piciform bird (noun)
bird with strong claws and a stiff tail adapted for climbing and a hard chisel-like bill for boring into wood for insects	any of numerous nonpasserine insectivorous climbing birds usually having strong bills for boring wood