to raise (oneself or another) from a recumbent to an upright or alert sitting posture
(intr) to remain out of bed and awake, esp until a late hour
informal (intr) to become suddenly interested or alert
devaluation of the dollar made the money market sit up
Rise to a sitting position from lying down, as in The sick child sat up and asked for a drink of water . [Early 1200s]
Stay up later than usual, as in The nurse sat up with her all night long . [Mid-1500s]
Sit with the spine erect, as in She was always telling the students to sit up . [Early 1700s]
Become suddenly alert, as in The students sat up when he brought up the test . The same sense appears in the related sit up and take notice , as in When he mentioned the arrival of a movie star, they all sat up and took notice . [Late 1800s]
First recorded in 1835–45; noun use of verb phrase sit up
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The test: Technically a curl-up, this exercise is a partial sit-up, done with your back in a C-shape and your arms crossed over your chest.
From Seattle Times ● Feb. 24, 2024
"A few things over the past few days have made people sit-up, realise the difficulties facing Rusal," an aluminium industry source said.
From Reuters ● Oct. 18, 2022
“We take a breath, and then when we do the sit-up, we exhale, and that relieves some of the pressure.”
From Scientific American ● Sep. 22, 2022
“Ow, that 50th sit-up – man, will I be paying ab-tax tomorrow!”
From Washington Post ● Apr. 28, 2022
The second sit-up was harder than the first, and the third was harder still.
From "The Contender" by Robert Lipsyte
She says she was able to sit up despite being covered by around six meters of rubble.
From Barron's ● Jul. 1, 2026
If there’s one thing in American sports that’s going to get people to sit up, lean forward and engage, it’s the home run.
From Los Angeles Times ● May 24, 2026
But even though “Reminders of Him” isn’t a great film, it’s a door-opener, a movie that will make both studio heads and screenwriters sit up and listen.
From Salon ● Mar. 19, 2026
It was a result that made you sit up straight.
From The Wall Street Journal ● Mar. 19, 2026
In any case I was finding it hard to sit up so long.
From "The Hiding Place" by Corrie ten Boom
Now I do 200 sit-ups, 120 push-ups and then these leg lifts.
From The Wall Street Journal ● May 25, 2026
Porciuncula also weaves in workouts on the deck, such as planks, sit-ups and crunches.
From Los Angeles Times ● Jan. 1, 2026
She claimed that one night Sharif kept Sara up all night doing sit-ups.
From BBC ● Dec. 11, 2024
For the core, find a patch of grass to do sit-ups.
From Seattle Times ● May 29, 2024
He did twenty sit-ups before he fell back exhausted.
From "The Contender" by Robert Lipsyte
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
