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Medical Dictionary


noun \ˈärch\

Medical Definition of arch

  1. 1:  an anatomical structure that resembles an arch in form or function: asa:  either of two vaulted portions of the bony structure of the foot that impart elasticity to it: (1):  a longitudinal arch supported posteriorly by the basal tuberosity of the calcaneus and anteriorly by the heads of the metatarsal bones (2):  a transverse arch consisting of the metatarsals and first row of tarsals and resulting from elevation of the central anterior portion of the median longitudinal archb:  arch of the aorta

  2. 2:  a fingerprint in which all the ridges run from side to side and make no backward turn

Illustration of arch

Seen and Heard

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a division or portion of a pool or whole

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