diminution vs reduction

diminution and reduction both are nouns.

Word	Noun	Adjective	Verb	Adverb
diminution	Yes	No	No	No
reduction	Yes	No	No	No

As nouns, diminution and reduction are synonyms defined as:

Other synonyms of diminution include decrease, step-down.

diminution (noun)	reduction (noun)
the act of decreasing or reducing something	the act of decreasing or reducing something
the statement of a theme in notes of lesser duration (usually half the length of the original)	the act of reducing complexity
change toward something smaller or lower	any process in which electrons are added to an atom or ion (as by removing oxygen or adding hydrogen); always occurs accompanied by oxidation of the reducing agent