oval vs elliptical

oval is a noun but elliptical is not a noun.

Word	Noun	Adjective	Verb	Adverb
oval	Yes	Yes	No	No
elliptical	No	Yes	No	No

As adjectives, oval and elliptical are synonyms defined as:

Other synonyms of oval include egg-shaped, elliptic, oval-shaped, ovate, oviform, ovoid, prolate.

oval (noun)	elliptical (noun)
a closed plane curve resulting from the intersection of a circular cone and a plane cutting completely through it

oval (adjective)	elliptical (adjective)
rounded like an egg	characterized by extreme economy of expression or omission of superfluous elements
	rounded like an egg