deflate

Short definition from Wiktionary

Verb

1. 1
   To remove air or some other gas from within an elastic container, e.g. a balloon or tyre.
2. 2
   To cause an object to decrease or become smaller in some parameter, e.g. to shrink
3. 3
   To reduce the amount of available currency or credit and thus lower prices.
4. 4
   To become deflated.
5. 5
   To let (someone) down, disappoint them, or put them in their place.
6. 6
   To compress (data) according to a particular algorithm.
7. 7
   To belch or flatulate