sea·​way ˈsē-ˌwā How to pronounce seaway (audio)
: the sea as a route for travel
also : an ocean traffic lane
: a moderate or rough sea
: a deep inland waterway that admits ocean shipping

Example Sentences

Recent Examples on the Web During the Late Cretaceous, much of the middle of North America — including the part of South Dakota where Sue and Galagadon were found — was intermittently flooded with an interior seaway. Gemma Tarlach, Discover Magazine, 21 Jan. 2019 Four hours later, waves moved through the Central American seaway and into the Pacific Ocean. Phillip Nieto, Fox News, 20 Oct. 2022 Wet, lowland habitats along the coasts of these subcontinents generally stood a better chance of preserving dinosaurs than areas that were more inland—until the seaway receded by 66 million years ago. Riley Black, Smithsonian Magazine, 19 Oct. 2022 Another key feature is that top speeds can be comfortably sustained in a seaway when typical planing yachts need to throttle back. Julia Zaltzman, Robb Report, 6 Oct. 2022 Ships must meet numerous safety and environmental requirements to traverse the lakes and have to be able to navigate the seaway’s 15-lock system to get to Lake Erie. Sylvia Goodman, Chicago Tribune, 17 July 2022 At the time, there was an inland seaway slowly withdrawing northward toward Canada, Woodruff said. Ashley Strickland, CNN, 10 Feb. 2022 But the new find from North Dakota indicates that large mosasaurs were still present in the last remaining parts of the ancient seaway in the middle of the continent. Riley Black, Smithsonian Magazine, 1 Nov. 2021 Back then, eastern New Mexico was covered by a seaway that extended deep into North America., 17 Apr. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seaway.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of seaway was before the 12th century

Dictionary Entries Near seaway

Cite this Entry

“Seaway.” Dictionary, Merriam-Webster, Accessed 26 Jan. 2023.

Kids Definition


sea·​way -ˌwā How to pronounce seaway (audio)
: a route for travel on the sea
: an ocean traffic lane
: a rough sea
: a deep inland waterway that admits ocean shipping

More from Merriam-Webster on seaway

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