a cataclysm resulting from a destructive sea wave caused by an earthquake or volcanic eruption; "a colossal tsunami destroyed the Minoan civilization in minutes"
an obvious change of public opinion or political sentiment that occurs without leadership or overt expression; "there was a ground swell of antiwar sentiment"
something that causes or entails suffering; "I cannot think it a hardship that more indulgence is allowed to men than to women"- James Boswell; "the many hardships of frontier life"
tank used for collecting and storing a liquid (as water or oil)
lake used to store water for community use
anything (a person or animal or plant or substance) in which an infectious agent normally lives and multiplies; "an infectious agent depends on a reservoir for its survival"
a large or extra supply of something; "a reservoir of talent"