sealed-beam

adjective

ˈsēl(d)-ˈbēm How to pronounce sealed-beam (audio)
: being an electric lamp with a prefocused reflector and lens sealed in the lamp vacuum

Word History

First Known Use

1939, in the meaning defined above

Time Traveler
The first known use of sealed-beam was in 1939

Dictionary Entries Near sealed-beam

sealed bank bill

sealed-beam

sealed book

See More Nearby Entries 

Cite this Entry

“Sealed-beam.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sealed-beam. Accessed 24 Dec. 2024.

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