expand extracts a file stored in a cabinet file (.cab).
wine expand source_file destination_file
source_file - file name of the cabinet file
destination_file - path and filename of file to be extracted.
Note: Wine's expand does not support all the command line options available from the Microsoft version of the tool.
There is a third party tool called cabextract available on many Linux distributions which supports many advanced features not yet supported by expand. Cabextract is free software under the GPL.
If you have a file called cow.cab which contains a file named moo.txt you could extract it with:
wine expand cow.cab moo.txt