arch (arches plural & 3rd person present) (arching present participle) (arched past tense & past participle )
1 n-count An arch is a structure that is curved at the top and is supported on either side by a pillar, post, or wall.
2 n-count An arch is a curved line or movement.
(=arc)
3 n-count The arch of your foot is the curved section at the bottom in the middle.
4 verb If you arch a part of your body such as your back or if it arches, you bend it so that it forms a curve.
Don't arch your back, keep your spine straight. V n, Also V
5 verb If you arch your eyebrows or if they arch, you move them upwards as a way of showing surprise or disapproval.
LITERARY
(=raise)
`Oh really?' he said, arching an eyebrow. V n, Also V