1. COMpression, file format> To create a COMpressed archive (a "zip file") from one or more files using PKWare' s PKZIP or a COMpatible archiver. Its use is spreading from MS-DOS now that portable implementations of the algorithm have been written. zip is also the name of a Unix archiving utility COMpatible with PKZIP. unzip is the corresponding de-archiver. See also gzip, tar and feather. 2. Zip Drive. [Jargon File] (1996-08-26)