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

The couple also drew inspiration from Montauk’s wild coastline, and the casual elegance of Europe’s seaside towns. Ariel Okin, Vogue, "The Designer Behind Surf Lodge and Sant Ambroeus Has Renovated a Montauk Beach House—and You Can Stay in It," 15 June 2018 All these drones could potentially collaborate and work together undetected providing reconnaissance, intelligence and surveillance on things like enemy coastlines and enemy fleets. Allison Barrie, Fox News, "Futuristic mini-sub could be a valuable weapon for Navy SEALs," 7 June 2018 Border Patrol agents can conduct immigration checks up to 100 miles from US land borders and coastlines. Catherine E. Shoichet, CNN, "The US border is bigger than you think," 23 May 2018 After all, Cuba’s coastlines and wildlife were eye-openers for our group. New York Times, "Want to See the Wild Side of Cuba? Try a Kayak," 16 May 2018 Ocean breezes, 70-plus miles of (almost) pristine coastline and sunshine galore. Carolina Gusman,, "14 biggest summer events in San Diego," 13 May 2018 To explore the Yakutat coastline and more remote sections of the park, hitch a ride on a bush plane or ferry. Andrea Sachs,, "This summer, stop by the 23 U.S. locales that have risen to become UNESCO World Heritage sites," 4 May 2018 While in Lake Como, Amal’s family enjoyed exploring the lake’s coastline and coves on chartered boat rides, provided by the lake’s Tassell fleet. Phil Boucher,, "In-Laws in Italy! Amal Clooney's Family Takes Over George's Lake Como Villa," 3 May 2018 Instead, Grazioli-DeAngelis points to an eroding coastline and more frequent hurricanes, as well as other predators. Avalon R. Zoppo,, "Foxes are disappearing from this Shore town, and residents finally know why," 27 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

23 Sep 2018

Look-up Popularity

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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Comments on coastline

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


evasion of direct action or statement

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