circular saw
 圓形鋸


 Saw, n.  An instrument for cutting or dividing substances, as wood, iron, etc., consisting of a thin blade, or plate, of steel, with a series of sharp teeth on the edge, which remove successive portions of the material by cutting and tearing.
 Note: ☞ Saw is frequently used adjectively, or as the first part of a compound.
 Band saw, Crosscut saw, etc. See under Band, Crosscut, etc.
 Circular saw, a disk of steel with saw teeth upon its periphery, and revolved on an arbor.
 Saw bench, a bench or table with a flat top for for sawing, especially with a circular saw which projects above the table.
 Saw file, a three-cornered file, such as is used for sharpening saw teeth.
 Saw frame, the frame or sash in a sawmill, in which the saw, or gang of saws, is held.
 Saw gate, a saw frame.
 Saw gin, the form of cotton gin invented by Eli Whitney, in which the cotton fibers are drawn, by the teeth of a set of revolving circular saws, through a wire grating which is too fine for the seeds to pass.
 Saw grass Bot., any one of certain cyperaceous plants having the edges of the leaves set with minute sharp teeth, especially the Cladium Mariscus of Europe, and the Cladium effusum of the Southern United States. Cf. Razor grass, under Razor.
 Saw log, a log of suitable size for sawing into lumber.
 Saw mandrel, a mandrel on which a circular saw is fastened for running.
 Saw pit, a pit over which timbor is sawed by two men, one standing below the timber and the other above. --Mortimer.
 Saw sharpener Zool., the great titmouse; -- so named from its harsh call note. [Prov. Eng.]
 Saw whetter Zool., the marsh titmouse (Parus palustris); -- so named from its call note. [Prov. Eng.]
 Scroll saw, a ribbon of steel with saw teeth upon one edge, stretched in a frame and adapted for sawing curved outlines; also, a machine in which such a saw is worked by foot or power.


 Cir·cu·lar a.
 1. In the form of, or bounded by, a circle; round.
 2. repeating itself; ending in itself; reverting to the point of beginning; hence, illogical; inconclusive; as, circular reasoning.
 3. Adhering to a fixed circle of legends; cyclic; hence, mean; inferior. See Cyclic poets, under Cyclic.
    Had Virgil been a circular poet, and closely adhered to history, how could the Romans have had Dido?   --Dennis.
 4. Addressed to a circle, or to a number of persons having a common interest; circulated, or intended for circulation; as, a circular letter.
    A proclamation of Henry III., . . . doubtless circular throughout England.   --Hallam.
 5. Perfect; complete. [Obs.]
 A man so absolute and circular
 In all those wished-for rarities that may take
 A virgin captive.   --Massinger.
 Circular are, any portion of the circumference of a circle.
 Circular cubics Math., curves of the third order which are imagined to pass through the two circular points at infinity.
 Circular functions. Math. See under Function.
 Circular instruments, mathematical instruments employed for measuring angles, in which the graduation extends round the whole circumference of a circle, or 360°.
 Circular lines, straight lines pertaining to the circle, as sines, tangents, secants, etc.
 Circular noteor Circular letter. (a) Com. See under Credit. (b) Diplomacy A letter addressed in identical terms to a number of persons.
 Circular numbers Arith., those whose powers terminate in the same digits as the roots themselves; as 5 and 6, whose squares are 25 and 36. --Bailey. --Barlow.
 Circular points at infinity Geom., two imaginary points at infinite distance through which every circle in the plane is, in the theory of curves, imagined to pass.
 Circular polarization. Min. See under Polarization.
 Circular sailing or Globular sailing Naut., the method of sailing by the arc of a great circle.
 Circular saw. See under Saw.


 circular saw
      n : a power saw that has a steel disk with cutting teeth on the
          periphery; rotates on a spindle [syn: buzz saw]