Learn oxidation and reduction with easy definitions, differences, examples, and daily life uses. Master redox reactions for exams and clear your chemistry basics. Learn the meaning of reduction as a noun and a verb, and see how it is used in different contexts. Find synonyms, related words, and pronunciation guides for reduction in British and American English. Synonyms for REDUCTION : deduction, discount, abatement, drop, decline, diminution, loss, depreciation; Antonyms of REDUCTION : addition, increase, gain, accession ... The percentage reduction formula is used to compare the decay in two quantities with different initial values. The percentage decrease formula is the ratio of the reduction in the quantity to its initial value multiplied by 100.