race (n.1) Look up race at Dictionary.com
"act of running," c.1300, from Old Norse ras "running, rush (of water)," cognate with Old English ræs, which became Middle English resen "attack, incursion," but did not survive into Modern English. Both the Norse and Old English words are from Proto-Germanic *ræs- (cf. Middle Dutch rasen "to rave, rage," German rasen). Originally a northern word, it became general in English c.1550. Meaning "contest of speed" first recorded 1510s. Race-horse is from 1620s.

Meaning "strong current of water" is from late 14c., possibly influenced by Old French raz, which had a similar meaning, and which probably is from Breton raz "a strait, narrow channel;" this French source also may have given race its meaning of "channel of a stream" (especially an artificial one to a mill), recorded from 1560s.
race (n.2) Look up race at Dictionary.com
"people of common descent," c.1500, from Middle French razza "race, breed, lineage," possibly from Italian razza, of unknown origin (cf. Spanish and Portuguese raza).

Original senses in English included "wines with characteristic flavor" (1520), "group of people with common occupation" (c.1500), and "generation" (c.1560). Meaning "tribe, nation, or people regarded as of common stock" is from c.1600. Modern meaning of "one of the great divisions of mankind based on physical peculiarities" is from 1774 (though even among anthropologists there never has been an accepted classification of these).
Just being a Negro doesn't qualify you to understand the race situation any more than being sick makes you an expert on medicine. [Dick Gregory, 1964]
Klein suggests these derive from Arabic ra's "head, beginning, origin" (cf. Hebrew rosh). Old English þeode meant both "race" and "language;" as a verb, geþeodan, it meant "to unite, to join." Race-riot attested from 1889, American English.
race (v.) Look up race at Dictionary.com
1670s, from race (n.1). In reference to an engine, from 1862. Related: Raced; racing.