rein

1 of 2

noun

Synonyms of reinnext
1
: a strap fastened to a bit by which a rider or driver controls an animal
usually used in plural
2
a
: a restraining influence : check
kept a tight rein on the proceedings
b
: controlling or guiding power
usually used in plural
the reins of government
3
: opportunity for unhampered activity or use
gave full rein to her imagination

Illustration of rein

Illustration of rein
  • R rein 1

rein

2 of 2

verb

reined; reining; reins

transitive verb

1
: to control or direct with or as if with reins
2
: to check or stop by or as if by a pull at the reins
reined in her horse
couldn't rein his impatience

intransitive verb

1
: to stop or slow up one's horse or oneself by or as if by pulling the reins
2
archaic : to submit to the use of reins

Examples of rein in a Sentence

Noun He has people working for him, but he has a tight rein on every part of the process. after the president resigned, the vice president stepped in and took the reins of the company Verb try to rein in your spending, so you have some money left for saving
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
After handing over the reins, Dimon will likely stay as executive chairman for a couple of years, the source said. Anirban Sen, USA Today, 29 June 2026 Qualcomm has long been known primarily as the maker of smartphone chips, but since taking the reins five years ago, CEO Cristiano Amon has worked to change that and equip the company for the tough but lucrative AI chip wars. Phil Wahba, Fortune, 27 June 2026
Verb
May will take over the Mavs as the team prepares for the second season with young superstar Coper Flagg, the reining NBA Rookie of the Year. Lawrence Dow, Fort Worth Star-Telegram, 22 June 2026 Smith's response was regarding a question about the expectation of LIV Golf having to rein things in financially with the Saudis officially pulling funding at the conclusion of the 2026 season. Mark Harris Outkick, FOXNews.com, 4 June 2026 See All Example Sentences for rein

Word History

Etymology

Noun

Middle English reine, from Anglo-French resne, reine, from Vulgar Latin *retina, from Latin retinēre to restrain — more at retain

First Known Use

Noun

13th century, in the meaning defined at sense 1

Verb

15th century, in the meaning defined at transitive sense 1

Time Traveler
The first known use of rein was in the 13th century

Browse Nearby Words

Cite this Entry

“Rein.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rein. Accessed 1 Jul. 2026.

Kids Definition

rein

1 of 2 noun
1
: a line or strap fastened to a bit on each side for controlling an animal (as a horse)
usually used in plural
2
a
: an influence that slows, limits, or holds back
kept the child under a tight rein
b
: controlling or guiding power
usually used in plural
seized the reins of government
3
: complete freedom : scope
gave full rein to her imagination

rein

2 of 2 verb
: to check, control, or stop by or as if by reins
reined in the horse
couldn't rein his impatience

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