up to

preposition10

1. •
   As much as; no more than (also with of).

   • You can make up to five copies.
   • Violators may face a fine of up to $300.
2. •
   Until.

   • Up to that point, I liked her.
   • I've read up to chapter 5.
3. •
   Within the responsibility of, to be attributed to the sphere of influence of, having someone or something as authoritative in.

   • It’s up to you whether to get the blue one or the red one.
   • It's up to the prosecution to prove that the defendant is guilty.
4. •
   Doing, involved in.

   • I have no idea what they've been getting up to while we've been away.
   • What are you up to today?
5. •
   Devising, scheming (planning something mischievous or inappropriate).

   • He looked like a man up to no good.
   • What are you kids up to with all that toilet paper?
6. •
   Capable, ready or equipped, having sufficient material preconditions for, possibly willpower (at a particular moment).

   • Are you up to lifting something that heavy?
   • Are you up to the challenge?
7. •
   Willing, interested in

   • Are you up to going to the beach?
8. •
   Considering all members of an equivalence class the same.

   • There’s only one rooted tree with two leaves, up to ordering.
9. •
   Taught by; in the class of.

   • I was up to Mr. Wayte, and, although he was a fairly easy and by no means strict master, […] — 1899
10. •
    (slang, no longer used) Familiar with the meaning of; able to understand.

adjective1

1. •
   Willing, interested in.

   • I'm feeling very up to it all of a sudden. — 2010

adjective1

1. •
   Doing something mischievous or scheming.

   • He looks like an angel, but I can tell he's up to something.