curvilineal vs curvilinear

curvilineal and curvilinear both are adjectives.

Word	Noun	Adjective	Verb	Adverb
curvilineal	No	Yes	No	No
curvilinear	No	Yes	No	No

As adjectives, curvilineal and curvilinear are synonyms defined as:

curvilineal and curvilinear: characterized by or following a curved line

curvilineal (adjective)	curvilinear (adjective)
characterized by or following a curved line	characterized by or following a curved line