hypo-

Hy"po-. Etym: [Gr. sub. See Sub-.] 1. A prefix signifying a less quantity, or a low state or degree, of that denoted by the word with which it is joined, or position under or beneath. 2. (Chem.) Defn: A prefix denoting that the element to the name of which it is prefixed enters with a low valence, or in a low state of oxidization, usually the lowest, into the compounds indicated; as, hyposulphurous acid.

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