Definition of "centerboard" [cen•ter•board]

• A movable keel in a sailboat that can be pivoted upward to reduce the boat's draft in shallow water. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "A centerboard is a wooden or metal fin housed in a centerboard trunk."
• "Of all things mechanical, he loved sailboats the most, planing into the wind with a sheet of canvas, a centerboard and a tiller, which he picked up from perusing the Horatio Hornblower novels."
• "By saving money, by earning more, and by each of us foregoing a bicycle on his birthday, we had collected the purchase price of the Mist, a beamy twenty-eight-footer, sloop-rigged, with baby topsail and centerboard."