drain
drained,
verb
1.
2.
3. To drink all the contents of: drained the cup.
4. a. To deplete gradually, especially to the point of complete exhaustion. See synonyms at deplete. b. To fatigue or spend emotionally or physically: The day's events completely drained me of all strength.
3.
4.
noun
3. The act or process of draining.
4. a. A gradual outflow or loss; consumption or depletion: the drain of young talent by emigration. b. Something that causes a gradual loss: interruptions that are a drain on my patience.
down the drain
To or into the condition of being wasted or lost: All of our best laid plans are down the drain.
[Middle English dreinen, to strain, drain, from Old English drēahnian.]