studdingsail

stud·ding·sail

 (stŭn′səl, stŭd′ĭng-sāl′)
n.
Any of several supplementary sails set from extensions of the yards of a square-rigged ship in light winds.

[Origin unknown.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

studdingsail

(ˈstʌdɪŋˌseɪl) (ˈstʌnsəl)
n
(Nautical Terms) nautical a light auxiliary sail set outboard on spars on either side of a square sail. Also called: stunsail or stuns'l
[C16: studding, perhaps from Middle Low German, Middle Dutch stōtinge, from stōten to thrust; related to German stossen]
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