\ ˈsit-ˌəp 
\
\Definition of sit-up
(Entry 1 of 2)
: 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
verbsat up; sitting up; sits up
Definition of sit up (Entry 2 of 2)
1a : 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
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More Definitions for sit-up
sit-up
nounEnglish Language Learners Definition of sit-up
: an exercise in which you lie on your back and use your stomach muscles to raise the top part of your body to a sitting position
See the full definition for sit-up in the English Language Learners Dictionary
sit-up
noun\ ˈsit-ˌəp \
Kids Definition of sit-up
: an exercise done by lying on the back and rising to a sitting position
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Time Traveler for sit-up
The first known use of sit-up was in the 13th century
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