minuscule vs miniscule

minuscule is a noun but miniscule is not a noun.

Word	Noun	Adjective	Verb	Adverb
minuscule	Yes	Yes	No	No
miniscule	No	Yes	No	No

As adjectives, minuscule and miniscule are synonyms defined as:

minuscule (noun)	miniscule (noun)
a small cursive script developed from uncial between the 7th and 9th centuries and used in medieval manuscripts
the characters that were once kept in bottom half of a compositor's type case

minuscule (adjective)	miniscule (adjective)
of or relating to a small cursive script developed from uncial; 7th to 9th centuries	extremely small
lowercase
extremely small