abzapfen

Etymology
16th century,.

Verb

 * 1)  of a liquid, to draw off, to tap
 * 2)  of blood, to draw
 * 3)  of something other than a liquid, to siphon off to take for oneself through morally or legally questionable means
 * 4)  to empty slowly by tapping continually
 * 1)  to empty slowly by tapping continually