What does "rapid" mean?

Rapid: Advancing with haste or speed; speedy in progression; in quick sequence; as, rapid growth; rapid improvement; rapid recurrence; rapid succession.

Additional senses

  1. 2.Quick in execution; as, a rapid penman.
  2. 3.The part of a river where the current moves with great swiftness, but without actual waterfall or cascade; -- usually in the plural; as, the Lachine rapids in the St. Lawrence. Row, brothers, row the stream runs fast, The rapids are near, and the daylight's past. Moore.

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