Source : Webster's Revised Unabridged Dictionary (1913)

Disarm \Dis*arm"\, v. t. [imp. & p. p. {Disarming}; p. pr. & vb.
   n. {Disarming}.] [OE. desarmen, F. d['e]sarmer; pref. d['e]s-
   (L. dis-) + armer to arm. See {Arm}.]
   1. To deprive of arms; to take away the weapons of; to
      deprive of the means of attack or defense; to render
      defenseless.

            Security disarms the best-appointed army. --Fuller.

            The proud was half disarmed of pride. --Tennyson.

   2. To deprive of the means or the disposition to harm; to
      render harmless or innocuous; as, to disarm a man's wrath.

Source : WordNet®

disarm
     v 1: remove offensive capability from [syn: {demilitarize}, {demilitarise}]
          [ant: {arm}]
     2: make less hostile; win over; "Her charm disarmed the
        prosecution lawyer completely"
     3: take away the weapons from; render harmless [syn: {unarm}]