apt - How do I search for available packages from the command-line? - Ask Ubuntu

To search for a particular package by name or description:

From the command-line, use:

apt-cache search keyword  

where the search keyword can be all or part of a package name or any words used in its description.

For example, apt-cache search proxy includes both these packages:

tinyproxy - A lightweight, non-caching, optionally anonymizing HTTP proxy  tircd - ircd proxy to the twitter API  

Note: the list may be long, so you can pipe the output to less to make it scrollable one line or one screen at a time, i.e. apt-cache search something | less.

To get a list of ALL packages

apt-cache search .

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