Mary,

Wouter explained it all. I just want to summarize:

-A rigid sail (with or without a separate mast) is a wingSAIL.
-A rigid streamlined rotating mast with a soft sail behind it is a wingMAST.
-Combinations of both exist, so these definitions are not final.

-WingSAILS use airplane wings terminology, slots, flaps, etc.
-WingMASTS with soft sails use normal terminology - except for the mast chord/rig chord % ratio.

-The chord of the rig in its foot is the foot length plus the mast chord. The mast chord is the length of its section.

PS - I don't know for sure is if the correct spelling is "Chord" or "Cord"...

PS2 - Bill Roberts worked in the development of wingsails and is certainly on of the best references, if not the best, on the subject.

PS3 - In my opinbion, unless new technical solutions to reef and fold rigid wingsails are developed, they are not practical for small cats. Wingmasts with bigger chords seem to be the best choice today, because very light masts can be built in carbon - weight was one of the main restrictions preventing wingmasts to have longer chord.