coast·​line | \-ˌlīn \

Definition of coastline 

1 : a line that forms the boundary between the land and the ocean or a lake

2 : the outline of a coast

Examples of coastline in a Sentence

The plane flew along the eastern coastline.

Recent Examples on the Web

Translation: Travelers can once again ride along the breathtaking coastline without any interruptions. Michelle Manetti, Good Housekeeping, "Weekend Travel Guide: Things to Do In California's Charming Carmel-by-the-Sea," 10 Aug. 2018 The most at risk areas, according to the map, are the western side of the state, where nearly every county along the Lake Michigan coastline is listed in red, and the Upper Peninsula, where more than half of the counties are in red. Susan Bromley, Detroit Free Press, "These Michigan counties are most at risk for Lyme disease," 3 Apr. 2018 The pipes could be installed all along the mainland coastline or integrated with the more than 4,000 oil production platforms in the region. Aristos Georgiou, Newsweek, "Scientists Are Planning to Stop Hurricanes in Their Tracks by Blowing Air Bubbles into the Sea," 21 Mar. 2018 The central coast trail is named for Amanda De-Cuys, an old, blind Native American woman who was removed from her home and forcibly marched along the coastline with a number of local tribe members., "Oregon state history hikes: 14 trails to celebrate Oregon's birthday," 14 Feb. 2018 The coastline is not visible from the fishing rafts and the numerous rompong are miles apart from one another, said Adilang's mother, Met Kahiking. Ali Kotarumalos, Fox News, "Indonesian teenager rescued after drifting 7 weeks at sea," 24 Sep. 2018 The coastline is not visible from the fishing rafts and the numerous rompong are miles apart, said Adilang’s mother, Net Kahiking. Ali Kotarumalos, The Seattle Times, "Indonesian teenager rescued after drifting 49 days at sea," 24 Sep. 2018 On a Geological Survey map of Louisiana, the coastline is a sea of red dots, each representative of oil and gas infrastructure. Gena Somra, CNN, "Louisiana's shrinking marshes signal the loss of a way of life," 6 June 2018 The same goes for the luxury market, particularly in leading sub-markets such as Malibu, where an eroding coastline has been a topic of conversation for years. Neal J. Leitereg,, "$110-million home sale in Malibu is set to be a new record for Los Angeles County," 24 Apr. 2018

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

1856, in the meaning defined at sense 1

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Statistics for coastline

Last Updated

2 Dec 2018

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Time Traveler for coastline

The first known use of coastline was in 1856

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English Language Learners Definition of coastline

: the land along the edge of a coast

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More from Merriam-Webster on coastline

Rhyming Dictionary: Words that rhyme with coastline

Spanish Central: Translation of coastline

Nglish: Translation of coastline for Spanish Speakers

Britannica English: Translation of coastline for Arabic Speakers Encyclopedia article about coastline

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a nest or breeding place

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