hypo : Idioms & Phrases

Hy"po-

Etymology

Gr. under, beneath; akin to L. sub. See Sub-.

Definitions

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.) 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.

Webster 1913

• noun a steel that contains less that 0.9% carbon
  

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