greedy vs grasping

greedy is not a noun while grasping is a noun.

Word	Noun	Adjective	Verb	Adverb
greedy	No	Yes	No	No
grasping	Yes	Yes	No	No

As adjectives, greedy and grasping are synonyms defined as:

Other synonyms of greedy include avaricious, covetous, grabby, prehensile.

greedy (noun)	grasping (noun)
	the act of gripping something firmly with the hands (or the tentacles)
	understanding with difficulty

greedy (adjective)	grasping (adjective)
immoderately desirous of acquiring e.g. wealth	immoderately desirous of acquiring e.g. wealth
(often followed by `for') ardently or excessively desirous
wanting to eat or drink more than one can reasonably consume