hemal arch vs haemal arch

hemal arch and haemal arch both are nouns.

Word	Noun	Adjective	Verb	Adverb
hemal arch	Yes	No	No	No
haemal arch	Yes	No	No	No

As nouns, hemal arch and haemal arch are synonyms defined as:

hemal arch and haemal arch: a structure arising ventrally from a vertebral centrum and enclosing the caudal blood vessels

hemal arch (noun)	haemal arch (noun)
a structure arising ventrally from a vertebral centrum and enclosing the caudal blood vessels	a structure arising ventrally from a vertebral centrum and enclosing the caudal blood vessels