amyloid vs amyloidal

amyloid is a noun but amyloidal is not a noun.

Word	Noun	Adjective	Verb	Adverb
amyloid	Yes	Yes	No	No
amyloidal	No	Yes	No	No

As adjectives, amyloid and amyloidal are synonyms defined as:

Other synonyms of amyloid include amylaceous, farinaceous, starchlike.

amyloid (noun)	amyloidal (noun)
(pathology) a waxy translucent complex protein resembling starch that results from degeneration of tissue
a non-nitrogenous food substance consisting chiefly of starch; any substance resembling starch

amyloid (adjective)	amyloidal (adjective)
resembling starch	resembling starch