Etymologically
Log in

coastline

History Permalink

Etymology and origin of the English word coastline

Confidence
Established
Formation
Compound
First attested
1761 Petition of Alexander, Duke of Gordon
Ultimate origins
Old French costeLatin līnea
Etymology tree
inherited borrowed derived
English coast
English coastline
From the same root
English coaster ← coast

Pronunciation

  • UK: /ˈkəʊstlaɪn/[1]
  • US: /ˈkoʊstlaɪn/[1]

Etymology

It is a compound from English coast + line.[2][3][4][5] Coast is from Old French coste (“rib, side; slope; shore”), from Latin costa (“a rib”);[3] line goes back to līnea (“linen thread, string”), partly through line and partly through Old French ligne.[3]

Earliest recorded meaning

The shape or outline of a coast, or the land along it: 1761, in a petition of Alexander, Duke of Gordon.[2]

Semantic evolution

The OED's first record, from 1761, is much earlier than the other dictionaries' dates: Etymonline gives 1819,[2][3] Merriam-Webster 1856[5] and Dictionary.com 1855–60.[4] The OED, which revised the entry in 2023, also records its use for the line that traces a coast on a map.[2] Merriam-Webster distinguishes the boundary line between land and water, a broad zone of land and water on both sides of a shoreline, and the general shape of the land along a coast.[5] Collins adds that the outline is especially as seen from the sea.[6]

Timeline

  • 1761 – the shape or outline of a coast; the land along it.[2]
  • 1819 – first date in Etymonline.[3]
  • 1856 – the boundary between land and sea, in Merriam-Webster.[5]

Meanings

Noun

  1. The line where the land meets the sea or a lake; the shoreline: The storm battered the whole eastern coastline.[5][2]
  2. The shape or outline of a coast, especially as seen from the sea, or as drawn on a map.[6][2][7]
  3. The land next to a coast.[6][2]
  4. A broad zone of land and water reaching both inland and out to sea from the shoreline.[5]

References

  1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
  3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  4. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
  5. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  6. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
  7. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin

Related etymologies

Cite this entry

“Coastline.” Etymologically, 31 Oct. 2026, etymologically.com/en/coastline. Accessed 31 Oct. 2026.

Last edited on . ·