coastline

noun

coast·​line ˈkōs(t)-ˌlīn 

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

The warnings were issued late Thursday and early Friday as meteorologists monitored lingering weather conditions along the coastline, stemming from remnants of regional tropical storms. — Noe Padilla, USA Today, 28 Aug. 2026

Her disappearance sparked a 24-hour search until her body was discovered during an aerial coastline survey. — Los Angeles Times, 27 Aug. 2026

Hiking trails lead to lookouts, while paddleboards allow for spontaneous exploration of the private island's coastline. — Cnt Editors, Condé Nast Traveler, 26 Aug. 2026

Towering waves generated by intense Pacific storm systems, their heights amplified by El Niño, could erode parts of the fragile coastline and shut down crucial coastal transportation arteries. — Andrew Freedman, CNN Money, 25 Aug. 2026

Word History

First Known Use

1856, in the meaning defined at sense 1

Rhymes for coastline

• affine
• airline
• align
• aline
• assign
• baseline
• beamline
• benign
• bloodline
• bovine
• brucine
• byline

Kids Definition

coastline

noun

coast·​line ˈkōst-ˌlīn 

: the outline or shape of a coast