close out

Short definition from Wiktionary

Verb

1. 1
   To terminate; to call the end of.
2. 2
   Synonym of close (“to make a sale”).
3. 3
   To settle, to pay what is due.
4. 4
   To break all at once, instead of progressively along its length.
5. 5
   To terminate a computer program.
6. 6
   To exclude by blocking all opportunities to enter or join.
7. 7
   To make trades offsetting an existing position, leaving the trader with a neutral position.
8. 8
   To seal off.