coast·​line | \ ˈkōs(t)-ˌlīn How to pronounce coastline (audio) \

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

That seemed like an appropriate description for this large, uniquely designed, sometimes less than graceful bird that is common to San Diego’s bays and coastlines. Ernie Cowan, San Diego Union-Tribune, "Pelican odd by design, graceful in flight," 13 June 2019 That’s the equivalent of setting five garbage bags full of trash on every foot of coastline around the world. Laura Parker, National Geographic, "The world's plastic pollution crisis explained," 12 June 2019 Homes were leveled, subways flooded, and coastlines destroyed; 2 million people were left without power. Kimberly Mas, Vox, "New York is building a wall to hold back the ocean," 11 June 2019 The authors compare how typical communities protected by smaller areas of mangrove (6m per metre of coastline average) fared over the long term versus communities with larger areas of mangroves (25m per metre average). Adam Moolna, Quartz India, "How mangroves could protect us from storms like Cyclone Fani," 7 June 2019 Walls of glass in the step-down living room take in 180-degree views of the Pacific and coastline. Lauren Beale,, "Singer Barry Manilow’s onetime beach house gets a remix in Malibu," 3 June 2019 As global temperatures increase and Arctic ice continues to shrink a shipping route roughly following Russia’s northern coastline becomes increasingly tenable. Kyle Mizokami, Popular Mechanics, "Meet 'Ural,' Russia's New Nuclear-Powered Icebreaking Behemoth," 28 May 2019 At nearly 130 feet tall, this historic lighthouse has stood proudly over the County Donegal coastline since 1817, an area known for its unspoiled nature and traditional Irish culture. Todd Plummer, Town & Country, "5 Amazing Locations in Ireland," 21 May 2019 One year ago, the Hawaiian volcano Kīlauea began erupting and continued for several months, eventually destroying hundreds of homes, displacing thousands of citizens, closing national parks, creating new islands, and changing Hawaii's coastline. Andrew Daniels, Popular Mechanics, "Turns Out You Can Fall 70 Feet Into Kīlauea Volcano and Survive," 3 May 2019

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

17 Jun 2019

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

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showing courage and determination

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