What is "flat arch"

Flat \Flat\ (fl[a^]t), a. [Compar. Flatter (fl[a^]t"r[~e]r); superl. Flattest (fl[a^]t"t[e^]st).] [Akin to Icel. flatr, Sw. flat, Dan. flad, OHG. flaz, and AS. flet floor, G. fl["o]tz stratum, layer.]

1. Having an even and horizontal surface, or nearly so, without prominences or depressions; level without inclination; plane.

   Though sun and moon Were in the flat sea sunk.
   --Milton.

2. Lying at full length, or spread out, upon the ground; level with the ground or earth; prostrate; as, to lie flat on the ground; hence, fallen; laid low; ruined; destroyed.

   What ruins kingdoms, and lays cities flat!
   --Milton.

   I feel . . . my hopes all flat.
   --Milton.

3. (Fine Arts) Wanting relief; destitute of variety; without points of prominence and striking interest.

   A large part of the work is, to me, very flat.
   --Coleridge.

4. Tasteless; stale; vapid; insipid; dead; as, fruit or drink flat to the taste.

5. Unanimated; dull; uninteresting; without point or spirit; monotonous; as, a flat speech or composition.

   How weary, stale, flat, and unprofitable Seem to me all the uses of this world.
   --Shak.

6. Lacking liveliness of commercial exchange and dealings; depressed; dull; as, the market is flat.

7. Clear; unmistakable; peremptory; absolute; positive; downright.

   Syn: flat-out.

   Flat burglary as ever was committed.
   --Shak.

   A great tobacco taker too, -- that's flat.
   --Marston.

8. (Mus.)

   1. Below the true pitch; hence, as applied to intervals, minor, or lower by a half step; as, a flat seventh; A flat.

   2. Not sharp or shrill; not acute; as, a flat sound.

9. (Phonetics) Sonant; vocal; -- applied to any one of the sonant or vocal consonants, as distinguished from a nonsonant (or sharp) consonant.

10. (Golf) Having a head at a very obtuse angle to the shaft; -- said of a club.

11. (Gram.) Not having an inflectional ending or sign, as a noun used as an adjective, or an adjective as an adverb, without the addition of a formative suffix, or an infinitive without the sign to. Many flat adverbs, as in run fast, buy cheap, are from AS. adverbs in -["e], the loss of this ending having made them like the adjectives. Some having forms in ly, such as exceeding, wonderful, true, are now archaic.

12. (Hort.) Flattening at the ends; -- said of certain fruits.

    Flat arch. (Arch.) See under Arch, n., 2. (b).

    Flat cap, cap paper, not folded. See under Paper.

    Flat chasing, in fine art metal working, a mode of ornamenting silverware, etc., producing figures by dots and lines made with a punching tool.
    --Knight.

    Flat chisel, a sculptor's chisel for smoothing.

    Flat file, a file wider than its thickness, and of rectangular section. See File.

    Flat nail, a small, sharp-pointed, wrought nail, with a flat, thin head, larger than a tack.
    --Knight.

    Flat paper, paper which has not been folded.

    Flat rail, a railroad rail consisting of a simple flat bar spiked to a longitudinal sleeper.

    Flat rods (Mining), horizontal or inclined connecting rods, for transmitting motion to pump rods at a distance.
    --Raymond.

    Flat rope, a rope made by plaiting instead of twisting; gasket; sennit.

    Note: Some flat hoisting ropes, as for mining shafts, are made by sewing together a number of ropes, making a wide, flat band.
    --Knight.

    Flat space. (Geom.) See Euclidian space.

    Flat stitch, the process of wood engraving. [Obs.] -- Flat tint (Painting), a coat of water color of one uniform shade.

    To fall flat (Fig.), to produce no effect; to fail in the intended effect; as, his speech fell flat.

    Of all who fell by saber or by shot, Not one fell half so flat as Walter Scott.
    --Lord Erskine.

n. an arch with mutually supporting voussoirs that has a straight horizontal extrados and intrados [syn: straight arch]