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1. A usually curved structure forming the upper edge of an open space and supporting the weight above it, as in a bridge or doorway.
2. A structure, such as a freestanding monument, shaped like an inverted U.
3. A curve with the ends down and the middle up: the arch of a raised eyebrow.
4. Anatomy An organ or structure having a curved or bowlike appearance, especially either of two arched sections of the bony structure of the foot.
v. arched, arch·ing, arch·es
1. To provide with an arch: arch a passageway.
2. To cause to form an arch or similar curve.
3. To bend backward: The dancers alternately arched and hunched their backs.
4. To span: "the rude bridge that arched the flood" (Ralph Waldo Emerson).
To form an arch or archlike curve: The high fly ball arched toward the stands.
[Middle English, from Old French arche, from Vulgar Latin *arca, from Latin arcus.]
1. Chief; principal: their arch foe.
a. Mischievous; roguish: "She ... was arch enough to inform the queen whenever I committed any folly that she thought would be diverting to her majesty" (Jonathan Swift).
b. Teasing, ironic, or sardonic: "I know, Edy Boardman said none too amiably with an arch glance from her shortsighted eyes. I know who is Tommy's sweetheart" (James Joyce).