arch 1
/ahrch/ , n.
1. Archit.
a. a curved masonry construction for spanning an opening, consisting of a number of wedgelike stones, bricks, or the like, set with the narrower side toward the opening in such a way that forces on the arch are transmitted as vertical or oblique stresses on either side of the opening.
b. an upwardly curved construction, as of steel or timber functioning in the manner of a masonry arch.
c. a doorway, gateway, etc., having a curved head; an archway.
d. the curved head of an opening, as a doorway.
2. any overhead curvature resembling an arch.
3. something bowed or curved; any bowlike part: the arch of the foot.
4. a device inserted in or built into shoes for supporting the arch of the foot.
5. a dam construction having the form of a barrel vault running vertically with its convex face toward the impounded water.
6. Glassmaking.
a. a chamber or opening in a glassmaking furnace.
b. See pot arch .
v.t.
7. to cover with a vault, or span with an arch: the rude bridge that arched the flood.
8. to throw or make into the shape of an arch or vault; curve: The horse arched its neck.
v.i.
9. to form an arch: elms arching over the road.
10. Naut. hog (def. 16).
[ 1250-1300; ME arch ( e ) arche arca, fem. var. of L arcus ARC ]
arch 2
/ahrch/ , adj.
1. playfully roguish or mischievous: an arch smile.
2. cunning; crafty; sly.
n.
3. Obs. a person who is preeminent; a chief.
[ independent use of ARCH- 1 ]