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SST

noun

ˌes-ˌes-ˈtē How to pronounce SST (audio)
: supersonic transport

Word History

Etymology

supersonic transport

First Known Use

1961, in the meaning defined above

Time Traveler
The first known use of SST was in 1961

Browse Nearby Words

SSS
SST
S star
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Cite this Entry

“SST.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/SST. Accessed 30 Nov. 2025.

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Kids Definition

SST

noun
ˌes-(ˌ)es-ˈtē How to pronounce SST (audio)
: an airplane used to transport people and goods at supersonic speeds
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