bitter pecan vs water hickory

bitter pecan and water hickory both are nouns.

Word	Noun	Adjective	Verb	Adverb
bitter pecan	Yes	No	No	No
water hickory	Yes	No	No	No

As nouns, bitter pecan and water hickory are synonyms defined as:

bitter pecan and water hickory: hickory of southern United States having many narrow leaflets and rather bitter nuts

Other synonyms of bitter pecan include Carya aquatica, water bitternut.

bitter pecan (noun)	water hickory (noun)
hickory of southern United States having many narrow leaflets and rather bitter nuts	hickory of southern United States having many narrow leaflets and rather bitter nuts