of one; the atoms of oxygen, nitrogen, and carbon are respectively dyads, triads, and tetrads, and have a
valence respectively of two, three, and four.
The valence of certain elements varies in different compounds. Valence in degree may extend as high
as seven or eight, as in the cases of iodine and osmium respectively. The doctrine of valence has been
of fundamental importance in distinguishing the equivalence from the atomic weight, and is an essential
factor in explaining the chemical structures of compounds.
Valencia
(Va*len"ci*a) n. [Perhaps fr. Valence in France.] A kind of woven fabric for waistcoats, having
the weft of wool and the warp of silk or cotton. [Written also valentia.]
Valenciennes lace
(Va*len`ci*ennes" lace") [F.; — so called after the town of Valenciennes.] A rich kind
of lace made at Valenciennes, in France. Each piece is made throughout, ground and pattern, by the
same person and with the same thread, the pattern being worked in the net.
Valency
(Val"en*cy) n.; pl. Valencies (Chem.) (a) See Valence. (b) A unit of combining power; a
so-called bond of affinity.
Valentia
(Va*len"ti*a) n. See Valencia.
Valentine
(Val"en*tine) n.
1. A sweetheart chosen on St. Valentine's Day.
2. A letter containing professions of love, or a missive of a sentimental, comic, or burlesque character,
sent on St. Valentine's Day.
St. Valentine's Day, a day sacred to St. Valentine; the 14th of February. It was a very old notion, alluded
to by Shakespeare, that on this day birds begin to mate. Hence, perhaps, arose the custom of sending
love tokens at that time.
Valentinian
(Val`en*tin"i*an) n. (Eccl. Hist.) One of a school of Judaizing Gnostics in the second century; —
so called from Valentinus, the founder.
Valeramide
(Val`er*am"ide) n. [Valeric + amide.] (Chem.) The acid amide derivative of valeric acid,
obtained as a white crystalline substance.
Valerate
(Val"er*ate) n. (Chem.) A salt of valeric acid.
Valerian
(Va*le"ri*an) n. [LL. valeriana, perhaps from some person named Valerius, or fr. L. valere to
be strong. powerful, on account of its medicinal virtues: cf. F. valériane.] (Bot.) Any plant of the genus
Valeriana. The root of the officinal valerian (V. officinalis) has a strong smell, and is much used in medicine
as an antispasmodic.
Greek valerian (Bot.), a plant (Polemonium cæruleum) with blue or white flowers, and leaves resembling
those of the officinal valerian.
Valerianaceous
(Va*le`ri*an*a"ceous) a. (Bot.) Of, pertaining to, or resembling, plants of a natural
order (Valerianaccæ) of which the valerian is the type. The order includes also the corn salads and the
oriental spikenard.
