fiduciary vs fiducial

fiduciary is a noun but fiducial is not a noun.

Word	Noun	Adjective	Verb	Adverb
fiduciary	Yes	Yes	No	No
fiducial	No	Yes	No	No

As adjectives, fiduciary and fiducial are synonyms defined as:

fiduciary and fiducial: relating to or of the nature of a legal trust (i.e. the holding of something in trust for another)

fiduciary (noun)	fiducial (noun)
a person who holds assets in trust for a beneficiary

fiduciary (adjective)	fiducial (adjective)
relating to or of the nature of a legal trust (i.e. the holding of something in trust for another)	relating to or of the nature of a legal trust (i.e. the holding of something in trust for another)
	used as a fixed standard of reference for comparison or measurement
	based on trust