R-value

noun
\ ˈär-ˌval-(ˌ)yü How to pronounce R-value (audio) \

Definition of R-value

: a measure of resistance to the flow of heat through a given thickness of a material (such as insulation) with higher numbers indicating better insulating properties — compare u-value

First Known Use of R-value

1948, in the meaning defined above

History and Etymology for R-value

probably from thermal resistance

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Time Traveler for R-value

Time Traveler

The first known use of R-value was in 1948

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Dictionary Entries Near R-value

RVA

R-value

RVer

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Statistics for R-value

Cite this Entry

“R-value.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/R-value. Accessed 24 May. 2022.

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