The Collaborative International Dictionary of English v.0.48:

cordless \cordless\ adj.
   1. operating without a wire connection to the companion
      communicating unit; -- of telephones and other devices
      using e.g. radio or infrared signals to allow
      communication between devices without a direct wire link;
      as, cordless telephones have a very restricted range
      compared with cellular phones.
      [PJC]

   2. using a battery as a source of power; -- of tools which
      usually use line current for power; as, cordless electric
      drills are very convenient for use outdoors; cordless
      razors make shaving while travelling easy.
      [PJC]

WordNet (r) 3.0 (2006):

cordless
    adj 1: not having a cord; "cordless telephone"