Junk Rig Glossary created and edited by the JRA Junk Rig Glossary editorial team:
http://junkrigassociation.org/page-1858532

Junk rig terms, a more basic introduction:
http://www.diy-wood-boat.com/Junk_Rig.html

General nautical terms:
http://en.wikipedia.org/wiki/Nautical_glossary