Source : Webster's Revised Unabridged Dictionary (1913)

Sahib \Sa"hib\, Saheb \Sa"heb\, n. [Ar. [,c][=a]hib master,
   lord, fem. [,c][=a]hibah.]
   A respectful title or appellation given to Europeans of rank.
   [India]

Source : WordNet®

sahib
     n : formerly a term of respect for important white Europeans in
         colonial India; used after the name