Rapid

a.	1.
	1.	Very swift or quick; moving with celerity; fast; as, a rapid stream; a rapid flight; a rapid motion. Ascend my chariot; guide the rapid wheels. - Milton.
	2.	Advancing with haste or speed; speedy in progression; in quick sequence; as, rapid growth; rapid improvement; rapid recurrence; rapid succession.
	3.	Quick in execution; as, a rapid penman.
n.	1.	The part of a river where the current moves with great swiftness, but without actual waterfall or cascade; sometimes called whitewater; - usually used 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.

Noun	1.	rapid - a part of a river where the current is very fast
Adj.	1.	rapid - done or occurring in a brief period of time; "a rapid rise through the ranks"
	2.	rapid - characterized by speed; moving with or capable of moving with high speed; "a rapid movment"; "a speedy car"; "a speedy errand boy" Synonyms: speedy

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