Sphenodon, sfē′nō-don, n. a genus of South American fossil sloths; a genus of extinct New Zealand lizards.—adj. Sphē′nodont. [Gr. sphēn, a wedge, odous, odontos, a tooth.]
Sphenoid, -al, sfē′noid, -al, adj. wedge-shaped: inserted like a wedge, denoting a bone at the base of the skull.—adjs. Spheneth′moid, pertaining to the sphenoid and the ethmoid bone; Sphē′nō-fron′tal, -mā′lar, -pal′atine, -parī′etal, -tem′poral, pertaining to the sphenoid and frontal, malar, palatine, parietal, and temporal bones respectively.—n. Sphē′nogram, a cuneiform character.—adjs. Sphēnograph′ic, -al.—n. Sphēnog′raphy, the art of writing or deciphering cuneiform inscriptions.—adjs. Sphēnot′ic, pertaining to the sphenoid bone and the otic capsule; Sphē′no-tur′binal, sphenoidal and turbinated or whorled. [Gr. sphēn, sphēnos, a wedge, eidos, form.]
Sphere, sfēr, n. a ball or globe: an orb or circle: circuit of motion: province or duty: definite range: rank, position in society: (geom.) a surface every point of which is equidistant from one and the same point, called the centre.—adjs. Sphēr′al; Sphere′less.—ns. Sphere′-met′al (Milt.), metal like that of which the celestial spheres were anciently supposed to be made; Sphere′-mū′sic, the music of the spheres.—adjs. Spher′ic, -al, pertaining to, or like, a sphere.—n. Spherical′ity.—adv. Spher′ically.—ns. Spher′icalness, Spheric′ity, state or quality of being spherical: roundness; Spher′icle, a little sphere; Spher′ics, the geometry and trigonometry of the sphere; Sphē′roid, a body or figure nearly spherical, but not quite so—a species of ellipsoid (prolate spheroid, a slightly lengthened sphere; oblate spheroid, a slightly flattened sphere).—adj. Sphēroi′dal, having the form of a spheroid.—ns. Sphēroidi′city, Sphēroid′ity, the state of being spheroidal; Sphē′romēre, one of the symmetrical segments of a radiate; Sphērom′eter, an instrument for measuring the sphericity of portions of spherical surfaces—for example, lenses; Sphē′rosid′erite, the name given to impure or earthy and frequently concretionary varieties of carbonate of iron.—adj. Spher′ūlar.—ns. Spher′ūle, a little sphere; Spher′ūlite, a radiating spherical group of minute acicular crystals common in silicious volcanic rocks.—adjs. Spherūlit′ic; Sphē′ry, spherical, round: belonging to the celestial spheres. [Fr.,—L. sphæra—Gr. sphaira.]
Sphex, sfeks, n. a genus of hymenopterous insects of the family Sphegidæ, closely allied to the true wasps (Vespidæ). [Gr. sphēx, a wasp.]
Sphincter, sfingk′tėr, n. (anat.) a muscle that contracts or shuts an orifice or opening which it surrounds—around the anus, &c.—adjs. Sphinc′terāte, provided with a sphincter, contracted as if by a sphincter; Sphinctē′rial, Sphincter′ic, relating to a sphincter or its function.—n. Sphincterot′omy, the operation of cutting a sphincter. [Gr. sphingktēr,—sphinggein, to bind tight.]
Sphinx, sfingks, n. a monster of Greek mythology, with the head of a woman and the body of a lioness, that proposed riddles to travellers, and strangled those who could not solve them: an enigmatic or inscrutable person: a hawk-moth: the Guinea baboon. [Gr.,—sphinggein, to throttle.]
Sphragistics, sfrā-jis′tiks, n. knowledge about seals, their age, history, &c. [Gr. sphragistikos, pertaining to seals—sphragis, a seal.]
Sphrigosis, sfri-gō′sis, n. in fruit-trees, excessive growth in wood and leaves at the expense of fruit. [Gr. sphrigan, to be vigorous.]
Sphygmograph, sfig′mō-graf, n. an instrument for ascertaining and recording the form, force, and frequency of the pulse-beat, and the changes it undergoes in certain morbid states.—adj. Sphyg′mic, pertaining to the pulse.—n. Sphyg′mogram, the record made by a sphygmograph.—adj. Sphygmograph′ic.—n. Sphygmog′raphy, the act of taking pulse-tracings.—adj. Sphyg′moid, pulse-like.—ns. Sphygmol′ogy, the science of the pulse; Sphygmōmānom′eter, Sphygmom′eter, an instrument for measuring the tension of blood in an artery; Sphyg′mophone, an instrument by means of which a pulse-beat makes a sound: Sphyg′mōscōpe, an instrument for making arterial pulsations visible; Sphyg′mus, the pulse. [Gr. sphygmos, the pulse, graphein, to write.]
Sphyrna, sfėr′na, n. a genus of hammer-headed sharks.—adj. Sphyr′nine. [Gr. sphyra, a hammer.]