Valueless
(Val"ue*less), a. Being of no value; having no worth.
Valuer
(Val"u*er) n. One who values; an appraiser.
Valure
(Val"ure) n. Value. [Obs.] Ld. Berners.
Valvasor
(Val"va*sor) n. (Feud. Law) See Vavasor.
Valvata
(||Val*va"ta) n. [NL.; cf. L. valvatus having folding doors. See Valve.] (Zoöl.) A genus of small
spiral fresh-water gastropods having an operculum.
Valvate
(Valv"ate) a. [L. valvatus having folding doors.]
1. Resembling, or serving as, a valve; consisting of, or opening by, a valve or valves; valvular.
2. (Bot.) (a) Meeting at the edges without overlapping; — said of the sepals or the petals of flowers in æstivation,
and of leaves in vernation. (b) Opening as if by doors or valves, as most kinds of capsules
and some anthers.
Valve
(Valve) n. [L. valva the leaf, fold, or valve of a door: cf. F. valve.]
1. A door; especially, one of a pair of folding doors, or one of the leaves of such a door.
Swift through the valves the visionary fair
Repassed.
Pope.
Heavily closed, . . . the valves of the barn doors.
Longfellow. 2. A lid, plug, or cover, applied to an aperture so that by its movement, as by swinging, lifting and falling,
sliding, turning, or the like, it will open or close the aperture to permit or prevent passage, as of a fluid.
A valve may act automatically so as to be opened by the effort of a fluid to pass in one direction, and
closed by the effort to pass in the other direction, as a clack valve; or it may be opened or closed by
hand or by mechanism, as a screw valve, or a slide valve.
3. (Anat.) One or more membranous partitions, flaps, or folds, which permit the passage of the contents
of a vessel or cavity in one direction, but stop or retard the flow in the opposite direction; as, the ileocolic,
mitral, and semilunar valves.
4. (Bot.) (a) One of the pieces into which a capsule naturally separates when it bursts. (b) One of
the two similar portions of the shell of a diatom. (c) A small portion of certain anthers, which opens like
a trapdoor to allow the pollen to escape, as in the barberry.
5. (Zoöl.) One of the pieces or divisions of bivalve or multivalve shells.
Air valve, Ball valve, Check valve, etc. See under Air. Ball, Check, etc. — Double-beat valve,
a kind of balance valve usually consisting of a movable, open-ended, turban-shaped shell provided with
two faces of nearly equal diameters, one above another, which rest upon two corresponding seats when
the valve is closed. — Equilibrium valve. (a) A balance valve. See under Balance. (b) A valve for
permitting air, steam, water, etc., to pass into or out of a chamber so as to establish or maintain equal
pressure within and without. — Valve chest (Mach.), a chamber in which a valve works; especially
(Steam Engine), the steam chest; — called in England valve box, and valve casing. See Steam chest,
under Steam. — Valve face (Mach.), that part of the surface of a valve which comes in contact with
