From WordNet (r) 2.0 (August 2003) [wn]:
audio
n 1: the audible part of a transmitted signal; "they always raise
the audio for commercials" [syn: sound]
2: an audible acoustic wave frequency [syn: audio frequency]
3: the sound elements of television
From The Collaborative International Dictionary of English v.0.48 [gcide]:
audio \audio\ n.
the part of a transmitted signal which conveys the sound of
the event represented by the signal, such as that of a
television program. "they always raise the audio for
commercials"
Syn: sound.
[WordNet 1.5]
2. 1 an audible acoustic wave frequency.
Syn: audio frequency
[WordNet 1.5]
3. the sound elements of television.
[WordNet 1.5]
From The Free On-line Dictionary of Computing (19 Sep 2003) [foldoc]:
audio
<file format> Sound, one component of multimedia. Computers
(and audio compact discs and digital audio tape) work with
digital audio, in contrast to vinyl disks or analogue tape.
(1999-07-30)