cow's head vs half-free morel

cow's head and half-free morel both are nouns.

Word	Noun	Adjective	Verb	Adverb
cow's head	Yes	No	No	No
half-free morel	Yes	No	No	No

As nouns, cow's head and half-free morel are synonyms defined as:

cow's head and half-free morel: a morel with the ridged and pitted fertile portion attached to the stipe for about half its length

Other synonyms of cow's head include Morchella semilibera.

cow's head (noun)	half-free morel (noun)
a morel with the ridged and pitted fertile portion attached to the stipe for about half its length	a morel with the ridged and pitted fertile portion attached to the stipe for about half its length