groundless vs unfounded

groundless and unfounded both are adjectives.

Word	Noun	Adjective	Verb	Adverb
groundless	No	Yes	No	No
unfounded	No	Yes	No	No

As adjectives, groundless and unfounded are synonyms defined as:

Other synonyms of groundless include baseless, idle, unwarranted, wild.

groundless (adjective)	unfounded (adjective)
without a basis in reason or fact	without a basis in reason or fact