rhombus vs parallelogram

rhombus and parallelogram both are nouns.

Word	Noun	Adjective	Verb	Adverb
rhombus	Yes	No	No	No
parallelogram	Yes	No	No	No

As nouns, parallelogram is a hypernym of rhombus; that is, parallelogram is a word with a broader meaning than rhombus:

rhombus: a parallelogram with four equal sides; an oblique-angled equilateral parallelogram
parallelogram: a quadrilateral whose opposite sides are both parallel and equal in length

rhombus (noun)	parallelogram (noun)
a parallelogram with four equal sides; an oblique-angled equilateral parallelogram	a quadrilateral whose opposite sides are both parallel and equal in length