minuscule - correct spelling
minuscule - adjective
Note: The word derives from the Latin minus meaning “less.” In much writing, you’ll find it spelled miniscule, probably because of the prefix mini- in the sense “of a small size.” Because of the frequency of miniscule, some usage panels consider miniscule a variant spelling rather than a misspelling.
Example: The minuscule amount of anthrax was enough to infect the entire city.
© Grammar.com