[1] : The Collaborative International Dictionary of English v.0.48

hypo \hy"po\, n.
   hypochondria. colloq.
   1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

hypo \hy"po\, n. abbrev. from hyposulphite. photog.
   sodium hyposulphite, or thiosulphate, a solution of which is
   used as a bath to wash out the unchanged silver salts in a
   picture. colloq.
   1913 webster

[3] : The Collaborative International Dictionary of English v.0.48

hypo- \hy"po-\ gr. ? under, beneath; akin to l. 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.
      1913 webster

   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.
      1913 webster
see also:
sub- 

[4] : WordNet (r) 2.0

hypo
     n 1: a compound used as a fixing agent in photographic developing
          syn: sodium thiosulphate, sodium thiosulfate
     2: a piston syringe that is fitted with a hypodermic needle for
        giving injections syn: hypodermic syringe, hypodermic
see also:
sodium thiosulphate sodium thiosulfate hypodermic syringe hypodermic 

Hypo- >> H Words
Hypo-, definition of term: Hypo-
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