The_navigator© wrote:
OED:

c. transf. Applied to something that is spread out like a sail,
or that catches the wind.

Note "c".

The dictionary, so far as I understand it, describes usages of words as part
of language, but not neccessarly a legal definition for the purpose of the
colregs (if the kitesail thingy is where this coming from / going).

Not saying it doesn't apply, though. On a canoe, the method of propulsion
isn't part of the vessel, but is a separate implement held and manipulated
by the person. Although not a direct correlate to the idea of whether a
sailboat can only be such if the sail is attached to it, it does suggest a
precedent for non-attachment of the means of propulsion. What about those
river ferry raft-things that are moved by the person on board pulling on a
rope stretched across the river? Aren't hey vessels?


--
Wally
www.makearatherlonglinkthattakesyounowhere.com
Things are always clearer in the cold, post-upload light.