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.
Ship traffic through the strait is well below pre-war levels due to the risk of attack if vessels don’t comply with an Iranian vetting regime near its coastline, which is in sharp contrast to the unhindered navigation before the war. — Matthew Lee, Los Angeles Times, 3 Sep. 2026 Stretches of coastline, colorful old quarters, modernist museums, and verdant parklands make up this vibrant melting pot. — Condé Nast Traveler, 3 Sep. 2026 Travelers can also check out beaches in nearby Wisconsin, which similarly has miles of coastline along both Lake Michigan and Lake Superior. — Evie Carrick, Travel + Leisure, 2 Sep. 2026 Working with the wedding planners of Stress and Success Events, the couple crafted an itinerary of celebrations in Taormina and along Sicily’s coastline. — Shelby Wax, Vogue, 1 Sep. 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 7 Sep. 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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