noun \ri-ˈdək-shən\

: the act of making something smaller in size, amount, number, etc. : the act of reducing something

: an amount by which something is reduced

Full Definition of REDUCTION

:  the act or process of reducing :  the state of being reduced
a :  something made by reducing
b :  the amount by which something is reduced
[Spanish reducción, from Latin reduction-, reductio] :  a South American Indian settlement directed by Jesuit missionaries
:  meiosis 2; specifically :  production of the gametic chromosome number in the first meiotic division
re·duc·tion·al \-shnəl, -shə-nəl\ adjective

Examples of REDUCTION

  1. a drastic reduction in size
  2. Many voters want to see some reduction of the deficit.
  3. There is a 20 percent reduction on selected items during this sale.


Middle English reduccion restoration, from Middle French reducion, from Late Latin & Latin; Late Latin reduction-, reductio reduction (in a syllogism), from Latin, restoration, from reducere
First Known Use: 15th century

Other Chemical Engineering Terms

alkali, cation, decant, hygroscopic, isotope, oxidize, slurry, solute, viscous


noun \ri-ˈdək-shən\   (Medical Dictionary)

Medical Definition of REDUCTION

: the replacement or realignment of a body part in normal position or restoration of a bodily condition to normal
: the process of reducing by chemical or electrochemical means
: the psychological diminishment of emotion or needs through activity or adjustment
: meiosis; specifically : production of the gametic chromosome number in the first meiotic division


noun    (Concise Encyclopedia)

Any of a class of chemical reactions in which the number of electrons associated with an atom or group of atoms is increased. The electrons taken up by the substance reduced are supplied by another substance, often hydrogen (H), which is thereby oxidized. See also oxidation-reduction.


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