The Subversion book covers the concept of vendor branches extensively: http://svnbook.red-bean.com/en/1.7/svn.advanced.vendorbr.html http://svnbook.red-bean.co

The Subversion book covers the concept of vendor branches extensively: http://svnbook.red-bean.com/en/1.7/svn.advanced.vendorbr.html http://svnbook.red-bean.com/en/1.7/svn.advanced.vendorbr.htm... That's where I first read the term, but it predates svn. As far as I know, it's been the common term for committing external dependencies to your own VCS for as long as there's been such a thing as a VCS.