sprężać

Etymology
From.

Verb

 * 1)  to tighten, to make taught
 * 2)  to compress gas
 * 3)  to flex
 * 4)  to mobilise oneself to do something
 * 5)  to become compressed
 * 1)  to mobilise oneself to do something
 * 2)  to become compressed
 * 1)  to become compressed