What does "metathesis" mean?

Metathesis: (Med.) A mere change in place of a morbid substance, without removal from the body.

Additional senses

  1. 2.(Chem.) The act, process, or result of exchange, substitution, or replacement of atoms and radicals; thus, by metathesis an acid gives up all or part of its hydrogen, takes on an equivalent amount of a metal or base, and forms a salt.

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