Dictionary

sit up

intransitive verb

Definition of SIT UP

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
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First Known Use of SIT UP

13th century

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2 ENTRIES FOUND:
Next Word in the Dictionary: sit–uponPrevious Word in the Dictionary: sit–upAll Words Near: sit up
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