rein

1 of 2

noun

ˈrān 

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

• 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

Synonyms of rein

Noun

• helm
• chair

Verb

• contain
• regulate
• curb
• control
• keep
• restrain

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

Noun

During the rein of the Assad dynasty, Alawites were overrepresented in government jobs and in the army and security forces. —CNN Money, 28 Dec. 2025

Some of that is because the technology isn’t fully baked, but some of it is because the end users—whether supply chain operators, store managers or consumers—aren’t ready to hand the reins to an AI model completely. —Meghan Hall, Sourcing Journal, 23 Dec. 2025

Verb

One local lawmaker recently filed a bill to rein them in. —Fred Schulte, Miami Herald, 30 Dec. 2025

The legal drama comes as Target seeks to right the ship on its wider business operations and turns the CEO reins over to company veteran Michael Fiddelke in February. —Glenn Taylor, Sourcing Journal, 26 Dec. 2025

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

Phrases Containing rein

• bearing rein
• free rein
• keep a rein on
• neck-rein
• rein in

Rhymes for rein

• ane
• bane
• blain
• brain
• cane
• chaine
• cheyne
• deign
• drain
• fain
• fane
• feign

Kids Definition

rein

1 of 2 noun

ˈrān 

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