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mainsail

American  
[meyn-seyl, meyn-suhl] / ˈmeɪnˌseɪl, ˈmeɪn səl /

noun

Nautical.
  1. the lowermost sail on a mainmast.


mainsail British  
/ ˈmeɪnsəl, ˈmeɪnˌseɪl /

noun

  1. nautical the largest and lowermost sail on the mainmast

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of mainsail

late Middle English word dating back to 1425–75; main 1, sail

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Fisher said he and Mettraux were under cover in the cockpit while sailing downwind with one reef in the mainsail when the boat nose-dived into a large wave and they heard a loud bang.

From Seattle Times

On the other boats, the helmsman has to dash around the back of the mainsail to the other side of the boat when it tacks or jibes.

From Seattle Times

American Magic seems to have particular control problems with its small rudder and when the mainsail is eased and it comes to the top mark powered up.

From Seattle Times

"A massive thank you to all the guys who helped," American Magic mainsail trimmer Paul Goodison told the New Zealand Herald.

From Fox News

It was also a traumatic experience for the crew, some of whom briefly were trapped under the giant mainsail when the 75-foot yacht tipped over on its port side.

From Seattle Times