Definition of aquanaut in US English:



  • A person who swims underwater using an aqualung.

    • ‘Joining the smart red and blue-liveried Maureen alone, I was, of course, interested in my fellow aquanauts: not least because one of them would become my buddy!’
    • ‘But a few less lucky aquanauts - 13 to be exact - have perished on the wreck in the last 20 years since it became accessible to recreational divers, five within the past three years.’
    • ‘From free diving in Tahiti with the natives to becoming one of the United States first aquanauts he has seen and done it all.’
    • ‘The aquanauts caught larvae at night, and the surface support team released them at mid-water to see where they headed - down to deeper waters, or up to shallower areas.’
    • ‘Among the competitors were many of the world's best pool distance swimmers and the planet's premier open water aquanauts.’
    • ‘We drop through what seems to be an eternal void, not five astronauts floating in space but five aquanauts in an expanse of emptiness.’
    • ‘As such, conditions are similar to those on the Moon or Mars, the aquanauts said.’
    • ‘And talk about challenges - the University of Maryland-bound aquanaut stands ‘maybe’ 5-feet tall with short arms, legs, small hands and feet.’
    • ‘A one-man submarine which can plunge to the icy depths of the sea allowing aquanauts access to a previously unreachable marine world has arrived in Hull to make a valuable addition to the city's rich maritime heritage.’
    • ‘For about $10,000 a day, aquanauts have access to the habitat - and the ocean - with all the comforts of home: six bunks, a shower, instant hot water, a microwave, a refrigerator, air conditioning and computers.’
    • ‘In calm waters, near a reef off New Providence Island, instructors teach novice aquanauts how to mount the SUB and then guide them into 15 feet of clear ocean to motor past coral reefs and brightly colored tropical fish.’
    • ‘Before reaching the entry point, the intrepid aquanaut, pink with exertion, has to pick his way delicately through a crowd of anglers armed with filleting knives before he can take an elegant step into the water.’


Late 19th century: from Latin aqua ‘water’ + Greek nautēs ‘sailor’.