sleeper

noun

sleep·​er ˈslē-pər 

1

: one that sleeps

2

: a piece of timber, stone, or steel on or near the ground to support a superstructure, keep railroad rails in place, or receive floor joists : stringpiece

3

: sleeping car

4

: someone or something unpromising or unnoticed that suddenly attains prominence or value

the low-budget film became the summer's sleeper

5

: children's pajamas usually with feet

—usually used in plural

6

chiefly British : a small earring or stud worn to keep the hole of a pierced ear from closing

7

: mole entry 2 sense 4

Synonyms

• dozer
• slumberer

Examples of sleeper in a Sentence

Sleepers were awakened by the sound of a loud crash.

He may turn out to be the sleeper in this year's election.

The movie was the summer's sleeper.

The movie became the sleeper hit of the summer.

Recent Examples on the Web

Of the online retailer’s best deals are the down alternative pillows that are designed with stomach sleepers in mind; the 20-piece nonstick cookware set that’s 50 percent off; and this swivel reclining chair with over 8,000 perfect reviews. —Megan Schaltegger, Southern Living, 1 Nov. 2024

The lumbar support is a great perk for back sleepers or those with back pain, but side sleepers may find that firmness a bit uncomfortable. —Macy Alcido, Architectural Digest, 31 Oct. 2024

DreamCloud mattresses are some of the best hybrid sleepers on the market. —Elsie Boskamp, USA TODAY, 29 Oct. 2024

This sunrise alarm clock gently rouses sleepers by mimicking the glow of dawn. —Malia Griggs, Glamour, 25 Oct. 2024

Word History

First Known Use

12th century, in the meaning defined at sense 1

Phrases Containing sleeper

• heavy sleeper
• light sleeper
• sleeper cell
• sleeper sofa
• sound sleeper

Kids Definition

sleeper

noun

sleep·​er ˈslē-pər 

1

: one that sleeps

2

: a horizontal beam to support something on or near ground level

3

: sleeping car

4

: someone or something considered unlikely to succeed that suddenly becomes successful