Metasomatism \Met`a*so"ma*tism\, n. [Pref. meta- + Gr. ?, ?,
body.] (Geol.)
An alteration in a mineral or rock mass when involving a
chemical change of the substance, as of chrysolite to
serpentine; -- opposed to ordinary metamorphism, as implying
simply a recrystallization. -- {Met`a*so*mat"ic}, a.
[1913 Webster]