tie up

Short definition from Wiktionary

Verb

1. 1
   To secure with rope, string, etc.
2. 2
   To occupy, detain, keep busy, or delay.
3. 3
   To complete, finish, or resolve.
4. 4
   To immobilize a capital: make a capital investment that makes that capital unavailable.

Noun

1. 1
   A temporary interruption or cessation of a normal activity.
2. 2
   The act of tying up (or immobilizing) a capital.
3. 3
   The connection of a loom's treadles to its shafts, used in combination with the threading and treadling to create a pattern.