su·​per·​firm ˌsü-pər-ˈfərm How to pronounce superfirm (audio)
: extremely firm
superfirm mattresses

Word History

First Known Use

1928, in the meaning defined above

Time Traveler
The first known use of superfirm was in 1928

Dictionary Entries Near superfirm

Cite this Entry

“Superfirm.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2024.

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