a cataclysm resulting from a destructive sea wave caused by an earthquake or volcanic eruption; "a colossal tsunami destroyed the Minoan civilization in minutes"
electro-acoustic transducer for converting electric signals into sounds; it is held over or inserted into the ear; "it was not the typing but the earphones that she disliked"
an obvious change of public opinion or political sentiment that occurs without leadership or overt expression; "there was a ground swell of antiwar sentiment"
being of crucial importance; "a pivotal event"; "Its pivotal location has also exposed it to periodic invasions"- Henry Kissinger; "the polar events of this study"; "a polar principal"