glass wool

noun

: glass fibers in a mass resembling wool and being used especially for thermal insulation and air filters

Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of glass wool was in 1879

Rhymes for glass wool

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Browse Nearby Words

glassware
glass wool
glasswork
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Cite this Entry

“Glass wool.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/glass%20wool. Accessed 5 Jul. 2026.

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Britannica.com: Encyclopedia article about glass wool

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