Word Origin & History
rapid1634, from L. rapidus "hasty, snatching," from rapere "hurry away, carry off, seize, plunder," from PIE base *rep- "to snatch" (cf. Gk. ereptomai "devour," harpazein "snatch away"). Rapids is 1765, from Fr. rapides, applied by Fr. voyagers to North American rivers. Rapid-transit first attested 1873;
rapid eye movement is from 1916.