decrease vs reduction

decrease and reduction both are nouns.

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

As nouns, decrease and reduction are synonyms defined as:

Other synonyms of decrease include diminution, step-down.

decrease (noun)	reduction (noun)
the act of decreasing or reducing something	the act of decreasing or reducing something
the amount by which something decreases	the act of reducing complexity
a change downward	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
a process of becoming smaller or shorter

decrease (verb)	reduction (verb)
decrease in size, extent, or range
make become smaller