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.
The group doesn’t control the part of Yemen’s coastline along Bab el-Mandeb but holds territory less than 60 miles away. — Fatma Khaled, Chicago Tribune, 8 Aug. 2026 Last week, the tides brought dangerous surf conditions to much of the coastline and damaged some of the protective measures put in place by cities. — Dean Fioresi, CBS News, 7 Aug. 2026 Yet the abundance of changes that has gone into crafting this successor seemingly justified a name change; from Roma, for the historic Italian capital, to Amalfi, after the famous craggy Italian coastline. — Howard Walker, Robb Report, 7 Aug. 2026 Most Mediterranean coastlines see some fire activity every August. — Christopher Elliott, Forbes.com, 7 Aug. 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 9 Aug. 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
Last Updated: - Updated example sentences
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