Source : Webster's Revised Unabridged Dictionary (1913)

Chaperon \Chap"er*on\, v. t. [imp. & p. p. {Chaperoned}; p. pr.
   & vb. n. {Chaperoning}.] [Cf. F. chaperonner, fr. chaperon.]
   To attend in public places as a guide and protector; to
   matronize.

         Fortunately Lady Bell Finley, whom I had promised to
         chaperon, sent to excuse herself.        --Hannah More.