Hy`po*plas"tron (?), n.; pl. Hypoplastra (#). [Pref. hypo- + plastron.]
(Anat.) The third lateral plate in the plastron of turtles; -- called
also hyposternum.
||Hy*pop"ti*lum (?), n.; pl. L. Hypoptila (#), E. Hypoptilums (#).
||[NL., fr. Gr. "ypo` beneath + &?; down.] (Zoˆl.) An accessory plume
||arising from the posterior side of the stem of the contour feathers
||of many birds; -- called also aftershaft. See Illust. of Feather.
||Hy`po*ra"di*us (?), n.; pl. Hyporadii (#). [Pref. hypo- + radius.]
||(Zoˆl.) One of the barbs of the hypoptilum, or aftershaft of a
||feather. See Feather.
||Hy`po*rha"chis (?), n.; pl. Hyporhachides (#). [NL., fr. Gr. "ypo`
||beneath + &?; spine.] (Zoˆl.) The stem of an aftershaft or
||hypoptilum. [Written also hyporachis.]
Hy`po*skel"e*tal (?), a. [Pref. hypo- + skeletal.] (Anat.) Beneath the
endoskeleton; hypaxial; as, the hyposkeletal muscles; -- opposed to
episkeletal.
||Hy`po*spa"di*as (?), n. [NL., fr. Gr. "ypo` beneath + spa`n to draw,
||tear.] (Med.) A deformity of the penis, in which the urethra opens
||upon its under surface.
Hy*pos"ta*sis (?), n.; pl. Hypostases (#). [L., fr. Gr. &?;
subsistence, substance, fr. &?; to stand under; &?; under + &?; to
stand, middle voice of &?; to cause to stand. See Hypo-, and Stand.] 1.
That which forms the basis of anything; underlying principle; a concept
or mental entity conceived or treated as an existing being or thing.
2. (Theol.) Substance; subsistence; essence; person; personality; --
used by the early theologians to denote any one of the three
subdivisions of the Godhead, the Father, Son, and Holy Spirit.
The Council of Alexandria (a. d. 362) defined hypostasis as synonymous
with person. Schaff- Herzog.
3. Principle; an element; -- used by the alchemists in speaking of
salt, sulphur, and mercury, which they considered as the three
principles of all material bodies.