1.
as far as a particular number, level, etc. :
I can take up to four people (= but no more than four) in my car.
The temperature went up to 35°C.
2.
(also up until sth ) not further or later than sth; until sth :
Read up to page 100.
Up to now he's been very quiet.
3.
as high or as good as sth :
Her latest book isn't up to her usual standard.
4.
(also up to doing sth ) physically or mentally capable of sth :
He's not up to the job.
I don't feel up to going to work today.
5.
( informal ) doing sth, especially sth bad :
What's she up to?
What've you been up to?
I'm sure he's up to no good (= doing sth bad) .