rem

1 of 2

noun (1)

ˈrem 

: 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  ˌär-ˌē-ˈem 

: rapid eye movement

Examples of rem in a Sentence

Recent Examples on the Web

Noun

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

McNamara's current research centers on the evolution of the frontal lobes, the evolution of the two mammalian sleep states (REM and NREM), and the evolution of religion in human cultures. — Big Think, 9 Apr. 2026

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

Phrases Containing rem

• ad rem
• in rem

Rhymes for rem

• clem
• em
• femme
• gem
• hem
• phlegm
• stem
• them
• atm
• diadem
• ibidem
• meristem

Kids Definition

REM

noun

ˈrem 

: rapid eye movement

Medical Definition

rem

1 of 2 noun

ˈrem 

: 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

REM

2 of 2 noun

ˈrem 

: rapid eye movement