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Something which rotates about an axis, as a wheel, or the drum of a capstan. "An axis or cylinder having a rundle about it." Bp. Wilkins.

Having the axis inclined to the base, as a cone.

The calcareous or hornlike coral forming the central stem or axis of most compound alcyonarians; -- called also foot secretion. See Illust. under Gorgoniacea, and Coenenchyma. -- Scler`o*ba"sic, a.

-- used chiefly for producing, when revolved, motion or pressure in the direction of its axis, by the sliding of the threads of the cylinder in the grooves between the threads of the perforation adapted to it, the former being distinguished as the external, or male screw, or, more usually the screw; the latter as the…

ry, performed after the constitutional effects of the injury have subsided. -- Secondary axis (Opt.), any line which passes through the optical center of a lens but not through the centers of curvature, or, in the case of a mirror, which passes through the center of curvature but not through the center of the mirror.…

A half column; a column bisected longitudinally, or along its axis.

The half of a lens divided along a plane passing through its axis.

and volition; -- applied to those nerve fibers which pass to and from the cerebro-spinal axis, and are respectively concerned in sensation and volition. Dunglison.

e valves of a pod break away from the partitions, and these remain attached to the common axis.

To turn about a fixed point, usually the center or axis, as a spar or piece of timber; to turn; -- used also of any heavy body.

An electrodynamic spiral having the conjuctive wire turned back along its axis, so as to neutralize that component of the effect of the current which is due to the length of the spiral, and reduce the whole effect to that of a series of equal and parallel circular currents. When traversed by a current the solenoid exhi…

Any one of the several symmetrical segments arranged around the central axis and composing the body of a radiate anmal.

A kind of flower cluster in which sessile flowers are arranged on an unbranched elongated axis. Spike grass (Bot.), either of two tall perennial American grasses (Uniola paniculata, and U. latifolia) having broad leaves and large flattened spikelets. -- Spike rush. (Bot.) See under Rush. -- Spike shell (Zoöl.), any p…

To move round rapidly; to whirl; to revolve, as a top or a spindle, about its axis. Round about him spun the landscape, Sky and forest reeled together. Longfellow. With a whirligig of jubilant mosquitoes spinning about each head. G. W. Cable.

astrics. -- Spinal column, the backbone, or connected series or vertebræ which forms the axis of the vertebrate skeleton; the spine; rachis; vertebral column. -- Spinal cord, the great nervous cord extending backward from the brain along the dorsal side of the spinal column of a vertebrate animal, and usually termina…

A slender rod or pin on which anything turns; an axis; as, the spindle of a vane. Specifically: --(a) (Mach.)

veral species of South American and Central American clamatorial birds belonging to Synallaxis and allied genera of the family Dendrocolaptidæ. They are allied to the ovenbirds.

Winding round a cylinder or imaginary axis, and at the same time rising or advancing forward; winding like the thread of a screw; helical.

The axis or receptacle in certain ferns (as Trichomanes), which bears the sporangia.

ur gear (Mach.), a cogwheel having teeth which project radially and stand parallel to the axis; a spur wheel. -- Spur gearing, gearing in which spur gears are used. See under Gearing. -- Spur pepper. (Bot.) See the Note under Capsicum. -- Spur wheel. Same as Spur gear, above.