Synonyms for Reduction (same or very similar meaning)
WordNet sense 1 (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):
reducing
WordNet sense 2 (the act of decreasing or reducing something):
decrease, diminution, step-down, decrease
WordNet sense 3 (the act of reducing complexity):
simplification
From the ODE community, based on WordNet
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