sitting up

Verb

sit up (third-person singular simple present sits up, present participle sitting up, simple past and past participle sat up)

1. (intransitive) To assume a sitting position from a position lying down.
   • Despite being cancer-ridden, Lorin sat up to greet the visitors.
2. (intransitive) To sit erect.
   • Sit up straight, mister!
3. (intransitive) To show sudden interest or surprise.
   • He sat up when we mentioned the increased pay package.
4. To bounce, especially to a comfortable height.
   • And within five minutes of the change United were level. Gabriel Obertan tuned his marker inside out and delivered a cross from the right that hit Hernandez and sat up perfectly for Owen to nod home.2011 January 29, Ian Hughes, “Southampton 1 - 2 Man Utd”, in BBC
5. To not go to bed (notionally remaining in a sitting position).
   • I sat up all night waiting for her to come home.
6. To stop pedalling hard.
   • Half way up the climb, Jones sat up and let Smith continue alone.

See all 7 meanings of sit up