1. A structure, especially one of masonry, forming the curved, pointed, or flat 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.
5. to provide with an arch: arch a passageway.
6. to cause to form an arch or similar curve.
7. to bend backward: the dancers alternately arched and hunched their backs.
8. to span: "the rude bridge that arched the flood” ( Ralph Waldo Emerson).
9. to form an arch or archlike curve: the high fly ball arched toward the stands.
10. chief; principal: their arch foe.
11. mischievous; roguish: an arch glance.

1. ​ knowing, clever, mischievous.
2. principal; primary.
3. an inverted U shape.
4. an arch-shaped arrangement of trapezoidal stones, designed to redistribute downward force outward.
5. an architectural element having the shape of an arch
6. an arc; a part of a curve.
7. to form into an arch shape

1. chief; eminent; greatest; principal.
2. cunning or sly; sportively mischievous; roguish.
3. any part of a curved line.
4.
5. usually a curved member made up of separate wedge-shaped solids, with the joints between them disposed in the direction of the radii of the curve; used to support the wall or other weight above an opening. in this sense arches are segmental, round (i. e., semicircular), or pointed.
6. A flat arch is a member constructed of stones cut into wedges or other shapes so as to support each other without rising in a curve.
7. any place covered by an arch; an archway.
8. any curvature in the form of an arch.
9. A chief.
10. to form into an arch; to curve.
11. to cover with an arch or arches.
12. to form or bend into the shape of an arch.

1. to cover with a vault, or span with an arch.
2. to throw into the shape of an arch or vault; curve: as, the horse arches his neck.
3. to form an arch or arches: as, the sky arches overhead.
4. chief; principal; preëminent. see arch-.
5. cunning; sly; shrewd; waggish; mischievous for sport; roguish: now commonly used of facial expression: as, “so arch a leer,”
6. A chief; a leader.
7. 1. in geometry, any part of the circumference of a circle or other curve; an arc. see arc
8. in architecture, a structure built of separate and inelastic blocks, assembled on a curved line in such a way as to retain their position when the structure is supported extraneously only at its two extremities.
9. any place covered with an arch or a vault like an arch: as, to pass through the arch of a bridge.
10. any curvature in the form of an arch: as, the arch of the aorta; the arch of an eyebrow, of the foot, of the heavens, etc.
11. in mining, a portion of a lode left standing, either as being too poor for profitable working or because it is needed to support the adjacent rock.
12. the roofing of the fire-chamber of a furnace, as a reverberatory or a glass-furnace; hence, sometimes, the fire-chamber itself.
13. A box or chest; in plural, archives.
14. the ark of noah.
15. the ark of the covenant.
16. chief; principal: a prefix much used in composition with words both of native and of foreign origin. see arch.

1. form an arch or curve
2. naughtily or annoyingly playful
3. a curved bony structure supporting or enclosing organs (especially the inner sides of the feet)
4. (architecture) a masonry construction (usually curved) for spanning an opening and supporting the weight above it
5. (used of behavior or attitude) characteristic of those who treat others with condescension
6. expert in skulduggery
7. a passageway under a curved masonry construction
8. a curved shape in the vertical plane that spans an opening