aqua·​naut ˈä-kwə-ˌnȯt How to pronounce aquanaut (audio)
: a scuba diver who lives and operates both inside and outside an underwater shelter for an extended period

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Aquanaut Has Greek Roots

Aquanaut combines aqua with the Greek nautes, meaning "sailor". Like astronaut and aeronaut, the word may remind you of those mythical Greek heroes known as the Argonauts, who sailed with Jason on his ship, the Argo, in quest of the Golden Fleece. Various underwater habitats for aquanauts, such as Conshelf, SEALAB, and MarineLab, have captured the public imagination since the 1960s.

Examples of aquanaut in a Sentence

Recent Examples on the Web The command ship’s first task was to find the deepest part of the Challenger Deep to ensure proper bragging rights for the aquanauts. Eliza Strickland, IEEE Spectrum, 29 Feb. 2012 Though Earle had applied for earlier missions in the Tektite program, women were excluded from participating; Earle's mission, Mission 6, was an all-female team of aquanauts. Stefanie Waldek, Condé Nast Traveler, 13 July 2023 The vehicle had dropped to about 9400 meters when a loud bang reverberated through the cabin, shaking the two aquanauts inside. Eliza Strickland, IEEE Spectrum, 29 Feb. 2012 The Continental Shelf program ran for several years and allowed aquanauts to live under the water off France and in the Red Sea. Dinah Voyles Pulver, USA TODAY, 10 May 2023 In 2002, Meir joined NASA’s aquanaut program, living under the surface of the ocean for five days. Eric Betz, Discover Magazine, 30 Oct. 2020 Eventually, Cameron’s aquanaut tendencies bled into his movie career. Michael Schulman, The New Yorker, 5 Apr. 2021 Last month, a crew of aquanauts and astronauts surfaced after spending nine days in an undersea habitat known as the Aquarius Reef Base, located 62 feet below the ocean surface off the coast of Key Largo, Florida. Emily Toomey, Smithsonian, 29 July 2019 Ari D’Agostino was joined by aquanaut Shirley Pomponi, a marine biologist at Harbor Branch Oceanographic Institute of Florida Atlantic University, and NASA astronaut candidate Jessica Watkins. Emily Toomey, Smithsonian, 29 July 2019

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'aquanaut.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Latin aqua + English -naut (as in aeronaut)

First Known Use

1881, in the meaning defined above

Time Traveler
The first known use of aquanaut was in 1881

Dictionary Entries Near aquanaut

Cite this Entry

“Aquanaut.” Dictionary, Merriam-Webster, Accessed 18 Apr. 2024.

Kids Definition


aqua·​naut ˈak-wə-ˌnȯt How to pronounce aquanaut (audio)
: a person who lives for a long while in an underwater shelter used as a base for research
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