tour (n.) Look up tour at Dictionary.com
c.1300, "a turn, a shift on duty," from Old French tor, tourn, tourn "a turn, trick, round, circuit, circumference," from torner, tourner "to turn" (see turn (v.)). Sense of "a continued ramble or excursion" is from 1640s. Tour de France as a bicycle race is recorded in English from 1916 (Tour de France Cycliste), distinguished from a motorcar race of the same name. The Grand Tour, a journey through France, Germany, Switzerland, and Italy formerly was the finishing touch in the education of a gentleman.
tour (v.) Look up tour at Dictionary.com
1746, "make a tour, travel about," from tour (n.). Related: Toured; touring.