Borrowed from French rapide, from Latin rapidus.

• (RP, America, Canada) IPA: /ˈɹæpɪd/

rapid

1. Very swift or quick.

   a rapid stream

   rapid growth

   rapid improvement

   • 1667, John Milton, “Book VI”, in Paradise Lost. […], London: […] [Samuel Simmons], and are to be sold by Peter Parker […]; [a]nd by Robert Boulter […]; [a]nd Matthias Walker, […], →OCLC ↗; republished as Paradise Lost in Ten Books: […], London: Basil Montagu Pickering […], 1873, →OCLC ↗:

     Ascend my Chariot; guide the rapid Wheeles.

   • 1921, Ben Travers, chapter 5, in A Cuckoo in the Nest, Garden City, N.Y.: Doubleday, Page & Company, published 1925, →OCLC ↗:

     The most rapid and most seductive transition in all human nature is that which attends the palliation of a ravenous appetite. There is something humiliating about it. […] Can those harmless but refined fellow-diners be the selfish cads whose gluttony and personal appearance so raised your contemptuous wrath on your arrival?

2. Steep, changing altitude quickly. (of a slope)
3. Needing only a brief exposure time. (of a lens, plate, film, etc.)
4. (England, dialectal) Violent, severe.
5. (obsolete, dialectal) Happy.

• French: rapide
• German: schnell
• Italian: rapido, deciso
• Portuguese: rápido
• Russian: бы́стрый
• Spanish: rápido

rapid

1. (archaic, colloquial) Rapidly.

rapid (plural rapids)

1. (usually, in the plural) A rough section of a river or stream which is difficult to navigate due to the swift and turbulent motion of the water.

   Coordinate term: riffle

2. (dated) A burst of rapid fire.
3. (chess) Short for rapid chess.

• French: rapides
• German: Stromschnelle
• Italian: rapida, cataratta
• Portuguese: corredeira
• Russian: стремни́на
• Spanish: rápido, rabión

• rapt