• Webster's Revised Unabridged Dictionary
    • n Disassimilation (Physics) The decomposition of complex substances, within the organism, into simpler ones suitable only for excretion, with evolution of energy, -- a normal nutritional process the reverse of assimilation; downward metabolism; -- now more commonly called catabolism. "The breaking down of already existing chemical compounds into simpler ones, sometimes called disassimilation ."
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Century Dictionary and Cyclopedia
    • n disassimilation The opposite of assimilation; specifically, the same as retrograde metamorphosis (which see, under metamorphosis) or catabolism.
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