The American Heritage® Desk Dictionary
by Editors of The American Heritage Dictionaries (Editor)
More than 70,000 entries, thoroughly revised and updated
More than 1,000 new words and meanings, from bioreserve and domestic partner to MP3 and 'zine
Expert guidance on correct English usage
Synonyms, regional notes, etymologies, and more
n. 1. An MPEG standard used especially for digitally transmitting music over the Internet.
2. A file containing a song or other audio data that is encoded using this standard: The band released its latest single as an MP3 on the Internet.