A retractable fin keel used on sailboats to prevent drifting to leeward

WordNet Word definitions in WordNet
n. a retractable fin keel used on sailboats to prevent drifting to leeward [syn: centerboard , drop keel , sliding keel ]

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
centreboard \centreboard\ n. same as centerboard . Syn: centerboard, drop keel, sliding keel.

Wiktionary Word definitions in Wiktionary
n. (context British spelling nautical English) The adjustable keel on a small yacht or dinghy that acts, among other things, as ballast and to counteract the sideways force of the wind.

Wikipedia Word definitions in Wikipedia
A centreboard or centerboard (US) is a retractable keel which pivots out of a slot in the hull of a sailboat , known as a centreboard trunk (UK) or centerboard case (US). The retractability allows the centreboard to be raised to operate in shallow waters, ...