amygdaloidal vs amygdaloid

amygdaloidal is not a noun while amygdaloid is a noun.

Word	Noun	Adjective	Verb	Adverb
amygdaloidal	No	Yes	No	No
amygdaloid	Yes	Yes	No	No

As adjectives, amygdaloidal and amygdaloid are synonyms defined as:

Other synonyms of amygdaloidal include almond-shaped, amygdaliform.

amygdaloidal (noun)	amygdaloid (noun)
	volcanic rock in which rounded cavities formed by expanding gas have subsequently become filled with mineral deposits

amygdaloidal (adjective)	amygdaloid (adjective)
shaped like an almond	shaped like an almond