knife up

Short definition from Wiktionary

Verb

1. 1
   To trim the edges on a boot or shoe of bits of leather, etc. that may be attached to the sides.
2. 2
   To trim with a knife.
3. 3
   To extract a morsel or dab (of something) with a knife.
4. 4
   To cut up or carve up with a knife.
5. 5
   To slice through; to cut or traverse a path through or between.
6. 6
   To penetrate sharply upward.
7. 7
   To move in a stabbing or penetrating manner
8. 8
   To traverse up the body in a quick stabbing sensation
9. 9
   To sit up or stand up suddenly.
10. 10
    To rise precipitously.