hy·​dro·​foil | \ˈhī-drə-ˌfȯi(-ə)l \

Definition of hydrofoil 

1 : a body similar to an airfoil but designed for action in or on water

2 : a motorboat that has metal plates or fins attached by struts fore and aft for lifting the hull clear of the water as speed is attained

Illustration of hydrofoil

Illustration of hydrofoil

hydrofoil 2

Examples of hydrofoil in a Sentence

Recent Examples on the Web

The Navy had studied hydrofoil ship concepts for two decades. Kyle Mizokami, Popular Mechanics, "When the U.S. Navy Had Tiny Hot Rods That Flew Over the Sea," 23 Dec. 2015 Still considered a prototype, the Surf Ranch wave is generated by a massive hydrofoil pulled along a track, displacing the water over an artificial reef. Hemal Jhaveri, For The Win, "How Kelly Slater took surfing out of the ocean and onto dry land," 3 July 2018 Those yachts, which could be equipped to hydrofoil in some conditions, would require smaller crews, probably no more than five sailors compared with the maximum of 10 that were used on the Volvo Ocean 65s this time. Christopher Clarey, New York Times, "Open Waters?," 21 June 2018 Mostly free of the drag imposed by sitting in liquid, a hydrofoil ship could go much faster than an ordinary vessel. Kyle Mizokami, Popular Mechanics, "When the U.S. Navy Had Tiny Hot Rods That Flew Over the Sea," 23 Dec. 2015 The episode playing in the Parr home depicts Jonny & Co. riding on water, directly setting up the massive hydrofoil yacht that serves as the setting for the climax of Incredibles 2. Josh Weiss, The Hollywood Reporter, "'Incredibles 2' TV References Are More Than Easter Eggs," 17 June 2018 The Gonet Monofoil is a revolutionary monohull that lifts out of the water on hydrofoils, the latest in sailing's surge into foiling technology. Rob Hodgetts, CNN, "Gonet Monofoil: Revolutionary 'flying' monohull takes off," 7 June 2018 The Coventry Lake Water Ski Club (CLWSC) will present the show and perform acts that include: barefooting, wakeboarding, pyramids, trick skiing, handle doubles, hydrofoil, and step-offs. Courant Community, "Community News For The Colchester Edition," 11 July 2017 Their pedaling powers the hydraulic systems used to trim the wingsail and raise and lower the daggerboards, or retractable centerboards, that are tipped with hydrofoils. Bernie Wilson, The Seattle Times, "Kiwis pedaling toward possible America’s Cup upset," 21 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hydrofoil.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of hydrofoil

1919, in the meaning defined at sense 1

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Time Traveler for hydrofoil

The first known use of hydrofoil was in 1919

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English Language Learners Definition of hydrofoil

: a very fast boat that rises partly out of the water when moving at high speeds

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Spanish Central: Translation of hydrofoil

Britannica.com: Encyclopedia article about hydrofoil

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