sit-up

1 of 2

noun

ˈsit-ˌəp 

: a conditioning exercise performed from a supine position by raising the torso to a sitting position and returning to the original position without using the arms or lifting the feet

sit up

2 of 2

verb

sat up; sitting up; sits up

intransitive verb

1

a

: to rise from a lying to a sitting position

b

: to sit with the back erect

2

: to show interest, alertness, or surprise

sit up and take notice

3

: to stay up after the usual time for going to bed

Examples of sit-up in a Sentence

Recent Examples on the Web

Noun

That includes an aerobic, strength, and core portion, including tests that assess timed runs, push-ups, and sit-ups. —Suzanne Blake, MSNBC Newsweek, 30 Sep. 2025

Physical fitness testing: Next, I was guided through a series of physical performance tests: max sit-ups, max push-ups, and a 3-minute plank. —Dana Ingemann, Health, 17 Sep. 2025

Verb

The bed is placed under the low ceiling of the eave, while the desk sits in the tallest part of the room, where there is space to sit up and walk around. —Abby Wolner, Better Homes & Gardens, 8 Oct. 2025

The next showed Milo now, sitting up in the back seat of the car and taking up an enormous amount of room—but the happy smile on his face and silky coat shows how much he's loved and cared for. —Rachael O'Connor, MSNBC Newsweek, 8 Oct. 2025

Word History

First Known Use

Noun

1900, in the meaning defined above

Verb

13th century, in the meaning defined at sense 1a

Rhymes for sit-up

• backup
• blowup
• breakup
• buildup
• checkup
• cleanup
• holdup
• hookup
• lineup
• lockup
• makeup
• markup

Kids Definition

sit-up

noun

ˈsit-ˌəp

: an exercise done by lying on the back and rising up to a sitting position by bending forward at the waist without lifting the feet and returning to the original position