coastline

noun

coast·​line ˈkōs(t)-ˌlīn How to pronounce coastline (audio)
Synonyms of coastlinenext
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Rosatom wants to bring nuclear power to that market, saying 38 of Africa’s 54 countries have coastlines suitable for its floating reactors. — Ruben Nyanguila, semafor.com, 30 Oct. 2026 Not far from Dublin’s Trinity College are the offices of Wild Atlantic Pictures, named after the 1,500-mile stretch of western Ireland’s rugged coastline. — Stacy Perman, Los Angeles Times, 29 Oct. 2026 Parts of Miami-Dade and Broward are under a coastal flood warning Wednesday as king tides continue to swamp South Florida’s coastline. — Milena Malaver, Miami Herald, 28 Oct. 2026 An itinerary of hikes, wine tastings, and a sunset cruise offering incredible views of the Santa Barbara coastline is a wonderful way to end the day, while a cozy house with a garden will add to everyone’s enjoyment. — Vogue, 27 Oct. 2026 See All Example Sentences for coastline

Word History

First Known Use

1856, in the meaning defined at sense 1

Time Traveler
The first known use of coastline was in 1856

Rhymes for coastline

See All Rhymes for coastline

Browse Nearby Words

coast lily
coastline
coast live oak
See all Nearby Words

Cite this Entry

“Coastline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/coastline. Accessed 1 Nov. 2026.

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Kids Definition

coastline

noun
coast·​line ˈkōst-ˌlīn How to pronounce coastline (audio)
: the outline or shape of a coast

More from Merriam-Webster on coastline

Thesaurus: All synonyms and antonyms for coastline

Britannica.com: Encyclopedia article about coastline

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