Defn: Sodium hyposulphite, or thiosulphate, a solution of which is used as a bath to wash out the unchanged silver salts in a picture. [Colloq.]

HYPOARIAN
Hy`po*a"ri*an, a. (Anat.)

Defn: Of or pertaining to a hypoarion.

HYPOARION
Hy`po*a"ri*on, n.; pl. Hypoaria. Etym: [NL., fr. Gr. (Anat.)

Defn: An oval lobe beneath each of the optic lobes in many fishes; one of the inferior lobes. Owen.

HYPOBLAST
Hy"po*blast, n. Etym: [Pref. hypo- + -blast.] (Biol.)

Defn: The inner or lower layer of the blastoderm; — called also endoderm, entoderm, and sometimes hypoderm. See Illust. of Blastoderm, Delamination, and Ectoderm.

HYPOBLASTIC
Hy`po*blas"tic, a. (Biol.)

Defn: Relating to, or connected with, the hypoblast; as, the hypoic sac.

HYPOBOLE
Hy*pob"o*le, n. Etym: [Gr. (Rhet.)