thun·​der·​head | \ˈthən-dər-ˌhed \

Definition of thunderhead 

: a rounded mass of cumulus or cumulonimbus cloud often appearing before a thunderstorm

Examples of thunderhead in a Sentence

A thunderhead was forming to the west.

Recent Examples on the Web

Puffs of thunderhead smoke rising between tower blocks. Louise Doughty, New York Times, "A War Correspondent Comes Home, Bringing War With Her," 20 Apr. 2018 On ordinary days, a pleasant wisp of white or a menacing thunderhead serve a more pedestrian preoccupation, a pragmatic barometer for how to dress or where to go. Amy Ellis Nutt, Washington Post, "From cloud nine to climate change, here’s why you should always look up," 7 Oct. 2017 And so the dysfunctionality grinds on, even as the thunderheads roll in and the water levels rise. Michelle Cottle, The Atlantic, "Can Congress Bring the National Flood Insurance Program Above Water?," 5 Aug. 2017 Lightning flashes sometimes occur at the tops of thunderheads, at elevations of 50,000 feet or higher. Chicago Tribune,, "Ask Tom: What is heat lightning?," 8 June 2017 Those thunderheads massing on the horizon let loose only a weak drizzle. Jennifer Senior, New York Times, "Review: A Teenager Bears Witness to Backwoods Intrigue in ‘History of Wolves’," 4 Jan. 2017 Off in the distance were puffy, juvenile thunderheads on the northeast horizon. Ernie Cowan Outdoors,, "Sit back and enjoy the show," 1 July 2017 In El Niño conditions, sea surface temperatures in the Pacific Ocean become unusually warm and tall thunderheads, known as cumulonimbus clouds, form over the water. Sindya N. Bhanoo, New York Times, "Study Shows Larger Effect of Clouds on El Niño," 4 Jan. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thunderhead.' 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 thunderhead

1843, in the meaning defined above

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Time Traveler for thunderhead

The first known use of thunderhead was in 1843

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English Language Learners Definition of thunderhead

: a very large cloud appearing before a thunderstorm


thun·​der·​head | \ˈthən-dər-ˌhed \

Kids Definition of thunderhead

: a rounded mass of dark cloud with white edges often appearing before a thunderstorm

More from Merriam-Webster on thunderhead

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Comments on thunderhead

What made you want to look up thunderhead? Please tell us where you read or heard it (including the quote, if possible).


something that serves to warn or remind

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