What does "camber" mean?

Camber: (Arch.) An upward concavity in the under side of a beam, girder, or lintel; also, a slight upward concavity in a straight arch. See Hogback. Camber arch (Arch.), an arch whose intrados, though apparently straight, has a slightly concave curve upward. -- Camber beam (Arch.), a beam whose under side has a concave curve upward.

Additional senses

  1. 2.To cut bend to an upward curve; to construct, as a deck, with an upward curve.
  2. 3.To curve upward.

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