1. Quick, fast, swift, rapid describe speedy tempo. Quick applies particularly to something practically instantaneous, an action or reaction, perhaps, of very brief duration: to give a quick look around; to take a quick walk. Fast and swift refer to actions, movements, etc., that continue for a time, and usually to those that are uninterrupted; when used of communication, transportation, and the like, they suggest a definite goal and a continuous trip. Swift, the more formal word, suggests the greater speed: a fast train; a swift message. Rapid, less speedy than the others, applies to a rate of movement or action, and usually to a series of actions or movements, related or unrelated: rapid calculation; a rapid walker. 10. See sharp.

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