rem

1 of 2

noun (1)

ˈrem How to pronounce rem (audio)
: the dosage of an ionizing radiation that will cause the same biological effect as one roentgen of X-ray or gamma-ray exposure

REM

2 of 2

noun (2)

ˈrem How to pronounce REM (audio) ˌär-ˌē-ˈem How to pronounce REM (audio)
: rapid eye movement

Examples of rem in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
That sense of individuality also informs REM’s scarcity strategy. — Tianwei Zhang, Footwear News, 25 Oct. 2026 Critical to healthy brain functioning is a dreaming state of unconsciousness called Rapid Eye Movement (REM) sleep. — Mike McRae 17, New Atlas, 17 Sep. 2026 Non-REM sleep makes up more of your sleep right after bedtime, and then REM becomes a higher proportion of sleep in the early morning hours. — Michael R. Nadorff, The Conversation, 14 Sep. 2026 Chronic snoozing would interrupt REM, an important time for brain health. — Jeff Wagner, CBS News, 8 Sep. 2026 See All Example Sentences for rem

Word History

Etymology

Noun (1)

roentgen equivalent man

First Known Use

Noun (1)

1947, in the meaning defined above

Noun (2)

1957, in the meaning defined above

Time Traveler
The first known use of rem was in 1947

Phrases Containing rem

Rhymes for rem

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Browse Nearby Words

rely on/upon
rem
REM
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Cite this Entry

“Rem.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rem. Accessed 1 Nov. 2026.

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Kids Definition

Medical Definition

rem

1 of 2 noun
ˈrem How to pronounce rem (audio)
: the dosage of an ionizing radiation that will cause the same biological effect as one roentgen of X-ray or gamma-ray dosage compare rep

More from Merriam-Webster on rem

Britannica.com: Encyclopedia article about rem

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