rapid

/ˈræpəd/

/ˈræpɪd/

Other forms: rapids

Rapid means happening with great speed or in a brief period of time. Think of Rapid Eye Movement (REM sleep), when your eyes are darting back and forth quickly — trying to follow your fast-paced dreams.

Rapid comes from the Latin word rapere, which means "to hurry away" or "to seize." If you are first to raise your hand in class with the correct answer, your teacher will be pleased with your rapid response. Your pulse may be rapid after you run a quick sprint, and after a rapid run-up in the stock market you may decide to sell some shares and lock in the profit.

Definitions of rapid

1. adjective

   characterized by speed; moving with or capable of moving with high speed
   “a rapid movement”

   synonyms: speedy

   fast

   acting or moving or capable of acting or moving quickly
2. adjective

   done or occurring in a brief period of time
   “a rapid rise through the ranks”

   synonyms:

   fast

   acting or moving or capable of acting or moving quickly
3. noun

   a part of a river where the current is very fast
   type of:

   waterway

   a navigable body of water