||Flu"or albus (?). [L., white flow.] (Med.) The whites; leucorrhÊa.
Flu`or*an"thene (?), n. [Fluorene + anthracene.] (Chem.) A white
crystalline hydrocarbon C15H10, of a complex structure, found as one
ingredient of the higher boiling portion of coal tar.
Flu"or*a`ted (?), a. (Chem.) Combined with fluorine; subjected to the
action of fluoride. [R.]
Flu`or*ene (?), n. (Chem.) A colorless, crystalline hydrocarbon, C13H10
having a beautiful violet fluorescence; whence its name. It occurs in
the higher boiling products of coal tar, and is obtained artificially.
Flu`o*res"ce*in (?), n. (Chem.) A yellowish red, crystalline substance,
C20H12O5, produced by heating together phthalic anhydride and resorcin;
-- so called, from the very brilliant yellowish green fluorescence of
its alkaline solutions. It has acid properties, and its salts of the
alkalies are known to the trade under the name of uranin.
Flu`o*res"cence (?), n. [From Fluor.] (Opt.) That property which some
transparent bodies have of producing at their surface, or within their
substance, light different in color from the mass of the material, as
when green crystals of fluor spar afford blue reflections. It is due
not to the difference in the color of a distinct surface layer, but to
the power which the substance has of modifying the light incident upon
it. The light emitted by fluorescent substances is in general of lower
refrangibility than the incident light. Stockes.
Flu`o*res"cent (?), a. Having the property of fluorescence.
Flu`o*res"cin (?), n. (Chem.) A colorless, amorphous substance which is
produced by the reduction of fluoresceÔn, and from which the latter may
be formed by oxidation.
Flu*or"ic (?), a. [Cf. F. fluorique.] (Chem.) Pertaining to, obtained
from, or containing, fluorine.
Flu"or*ide (? or ?; 104), n. [Cf. F. fluoride.] (Chem.) A binary
compound of fluorine with another element or radical.
Calcium fluoride (Min.), fluorite, CaF2. See Fluorite.
Flu"or*ine (fl"r*n or -n; 104), n. [NL. fluorina: cf. G. fluorin, F.
fluorine. So called from its occurrence in the mineral fluorite.]
(Chem.) A non-metallic, gaseous element, strongly acid or negative, and
associated with chlorine, bromine, and iodine, in the halogen group of
which it is the first member. It always occurs combined, is very active
chemically, and possesses such an avidity for most elements, and
silicon especially, that it can neither be prepared nor kept in glass
vessels. If set free it immediately attacks the containing material, so
that it was not isolated until 1886. It is a pungent, corrosive,
colorless gas. Symbol F. Atomic weight 19.
Fluorine unites with hydrogen to form hydrofluoric acid, which is the
agent employed in etching glass. It occurs naturally, principally
combined as calcium fluoride in fluorite, and as a double fluoride of
aluminium and sodium in cryolite.
Flu"or*ite (?), n. (Min.) Calcium fluoride, a mineral of many different
colors, white, yellow, purple, green, red, etc., often very beautiful,
crystallizing commonly in cubes with perfect octahedral cleavage; also
massive. It is used as a flux. Some varieties are used for ornamental
vessels. Also called fluor spar, or simply fluor.
Flu"or*oid (?), n. [Fluor + - oid.] (Crystallog.) A tetrahexahedron; --
so called because it is a common form of fluorite.
Flu*or"o*scope (?), n. [Fluorescence + -scope.] (Phys.) An instrument
for observing or exhibiting fluorescence.
Flu"or*ous (?), a. Pertaining to fluor.
Flu"or spar` (?). (Min.) See Fluorite.
Flu`o*sil"i*cate (?), n. [Cf. F. fluosilicate.] (Chem.) A double
fluoride of silicon and some other (usually basic) element or radical,
regarded as a salt of fluosilicic acid; -- called also silicofluoride.
Flu`o*si*lic"ic (?), a. [Fluo- + silicic: cf. F. fluosilicique.]
(Chem.) Composed of, or derived from, silicon and fluorine.
Fluosilicic acid, a double fluoride of hydrogen and silicon, H2F6Si,
obtained in solution in water as a sour fuming liquid, and regarded as
the type of the fluosilicates; -- called also silicofluoric acid, and
hydrofluosilicic acid.
Flur"ried (?), a. Agitated; excited. -- Flur"ried*ly adv.
Flur"ry (?), n.; pl. Flurries (#). [Prov. E. flur to ruffle.] 1. A
sudden and brief blast or gust; a light, temporary breeze; as, a flurry
of wind.