What does "calcar" mean?

Calcar: (Bot.) A hollow tube or spur at the base of a petal or corolla.

Additional senses

  1. 2.(Zoöl.) A slender bony process from the ankle joint of bats, which helps to support the posterior part of the web, in flight.
  2. 3.(Anat.) (a) A spur, or spurlike prominence. (b) A curved ridge in the floor of the leteral ventricle of the brain; the calcar avis, hippocampus minor, or ergot.

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