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

At the time it was eliminated in 2012, the Presidential Fitness Test included a one-mile run, sit-ups, a shuttle run, a sit-and-reach test, and pull-ups or push-ups. —Nuria Martinez-Keel, Oklahoma Voice, 8 Jan. 2026

There are distance runs and sprints, long circuits of sit-ups, tire throws, box jumps, ladders and bag work, followed by sparring several nights a week with kids whose parents drive them in from Killeen, San Antonio, Uvalde or Laredo. —Emiliano Tahui Gómez, Austin American Statesman, 28 Dec. 2025

Verb

Getting back in the chutes Kippes’ introduction to bull riding came at 5, sitting up high inside the Denver Coliseum, watching the National Western Stock Show. —Kyle Newman, Denver Post, 22 Jan. 2026

One mom set up a full Mexican buffet, complete with a piñata—for a group of 6-month-olds who couldn't even sit up, let alone swing a stick. —Lauren Brown West-Rosenthal, Parents, 7 Jan. 2026

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