Micraster
(||Mi*cras"ter) n. [NL., fr. Gr. mikro`s small + star.] (Paleon.) A genus of sea urchins, similar
to Spatangus, abounding in the chalk formation; — from the starlike disposal of the ambulacral furrows.
Micrencephalous
(Mi`cren*ceph"a*lous) [Micr- + Gr. brain.] Having a small brain.
Micro-
(Mi"cro- Mi"cr-). [Gr. mikro`s small.] A combining form signifying: (a) Small, little, trivial, slight; as,
microcosm, microscope. (b) (Metric System, Elec., Mech., etc.) A millionth part of; as, microfarad,
microohm, micrometer.
Microampère
(Mi`cro*am`père") n. [Micr- + ampère.] (Elec.) One of the smaller measures of electrical
currents; the millionth part of one ampère.
Microbacteria
(||Mi`cro*bac*te"ri*a) n. pl. [NL. See Micro-, and Bacterium.] (Biol.) In the classification
of Cohn, one of the four tribes of Bacteria.
In this classification bacteria are divided into four tribes: 1. Spherobacteria, or spherical bacteria, as
the genus Micrococcus. 2. Microbacteria, or bacteria in the form of short rods, including the genus
Bacterium. 3. Desmobacteria, or bacteria in straight filaments, of which the genus Bacillus is a type.
4. Spirobacteria, or bacteria in spiral filaments, as the genus Vibrio.
Microbe
(Mi"crobe ||Mi*cro"bi*on) n. [NL. microbion, fr. Gr. little + life.] (Biol.) A microscopic organism; —
particularly applied to bacteria and especially to pathogenic forms; as, the microbe of fowl cholera.
Microbian
(Mi*cro"bi*an) a. (Biol.) Of, pertaining to, or caused by, microbes; as, the microbian theory; a
microbian disease.
Microbic
(Mi*crob"ic) a. (Biol.) Of or pertaining to a microbe.
Microbicide
(Mi*crob"i*cide) n. [Microbe + L. caedere to kill.] (Biol.) Any agent detrimental to, or destructive
of, the life of microbes or bacterial organisms.
Microcephalic
(Mi`cro*ce*phal"ic Mi`cro*ceph"a*lous) a. [Micro- + cephalic, cephalous.] (Anat.) Having
a small head; having the cranial cavity small; — opposed to megacephalic.
Micro-chemical
(Mi`cro-chem"ic*al) a. Of or pertaining to micro-chemistry; as, a micro-chemical test.
Micro-chemistry
(Mi`cro-chem"is*try) n. [Micro- + chemistry.] The application of chemical tests to
minute objects or portions of matter, magnified by the use of the microscopy; — distinguished from macro-
chemistry.
Microchronometer
(Mi`cro*chro*nom"e*ter) n. A chronoscope.
Microcline
(Mi"cro*cline) n. [Micro- + Gr. to incline.] (Min.) A mineral of the feldspar group, like orthoclase
or common feldspar in composition, but triclinic in form.
Micrococcal
(Mi`cro*coc"cal) a. Of or pertaining to micrococci; caused by micrococci. Nature.
Micrococcus
(||Mi`cro*coc"cus) n.; pl. Micrococci [NL. See Micro-, and Coccus.] (Biol.) A genus of
Spherobacteria, in the form of very small globular or oval cells, forming, by transverse division, filaments,
or chains of cells, or in some cases single organisms shaped like dumb-bells all without the power of
motion. See Illust. of Ascoccus.
Physiologically, micrococci are divided into three groups; chromogenic, characterized by their power of
forming pigment; zymogenic, including those associated with definite chemical processes; and pathogenic,
those connected with disease.
