Merriam-Webster's Collegiate® Dictionary, 11th Edition
TOUR
I. noun see: turn
Date: 14th century
1. one's turn in an orderly schedule ; shift , a period during which an individual or unit is on a specific duty or at one place ,
2. a journey for business, pleasure, or education often involving a series of stops and ending at the starting point, a brief turn ; round , a series of professional tournaments (as in golf or tennis),
II. verb
Date: 1708
intransitive verb to make a tour, transitive verb to make a tour of, to present (as a theatrical production) on a tour