Functioning and Rapid

functioning

Process or manner of functioning or operating.
- usage: "the power of its engine determines its operation"; "the plane's operation in high winds"; "they compared the cooking performance of each oven"; "the jet's performance conformed to high standards"
- synonyms: operation, performance

Perform as expected when applied.
- usage: "The washing machine won't go unless it's plugged in"; "Does this old car still run well"; "This old radio doesn't work anymore"
- synonyms: function, work, operate, go, run
Serve a purpose, role, or function.
- usage: "The tree stump serves as a table"; "The female students served as a control group"; "This table would serve very well"; "His freedom served him well"; "The table functions as a desk"
- synonyms: serve, function
Perform duties attached to a particular office or place or function.
- usage: "His wife officiated as his private secretary"
- synonyms: officiate, function

Performing or able to perform its regular function.
- usage: "a functioning flashlight"

rapid

Done or occurring in a brief period of time.
- usage: "a rapid rise through the ranks"
Characterized by speed; moving with or capable of moving with high speed.
- usage: "a rapid movement"; "a speedy car"; "a speedy errand boy"
- synonyms: speedy

(a.) Quick in execution; as, a rapid penman.
(a.) Very swift or quick; moving with celerity; fast; as, a rapid stream; a rapid flight; a rapid motion.
(a.) 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.
(a.) Advancing with haste or speed; speedy in progression; in quick sequence; as, rapid growth; rapid improvement; rapid recurrence; rapid succession.

Webster's Revised Unabridged Dictionary