What does "diameter" mean?

Diameter: The length of a straight line through the center of an object from side to side; width; thickness; as, the diameter of a tree or rock. Note: In an elongated object the diameter is usually taken at right angles to the longer axis.

Additional senses

  1. 2.(Arch.) The distance through the lower part of the shaft of a column, used as a standard measure for all parts of the order. See Module. Conjugate diameters. See under Conjugate.

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