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

In a state bordered on three sides by water, Floridians understand what our coastlines mean. —Anna V. Eskamani, The Orlando Sentinel, 24 May 2026

The destroyer has been deployed to multiple regions globally, with operations heavily focused on the Middle East, the Indo-Pacific, and most recently, the Caribbean and North American coastline. —Kaif Shaikh, Interesting Engineering, 22 May 2026

Waterfalls, volcanic terrain and open coastlines are frequently described as emotionally restorative for travelers seeking space and reflection. —Hanna Wickes, Kansas City Star, 21 May 2026

The neighborhood/area Cam Ranh’s coastline is still developing, meaning there’s less buzzy nightlife and more quiet sunrise strolls along the nine-mile Bai Dai Beach. —Condé Nast, Condé Nast Traveler, 20 May 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