- A system for the reduction of noise in audio recordings. One variation involves providing additional gain for certain frequencies during recording, and reducing said gain during playback. May be used, for instance, in tape decks. Also called Dolby noise reduction, Dolby noise reduction system, or Dolby system.
- A multiple-channel sound format which is digitally encoded, and which provides up to six channels of surround sound. Also called Dolby surround sound, Dolby surround, Dolby digital surround, Dolby digital.