standing wave: a wave (as a sound wave in a chamber or an electromagnetic wave in a transmission line) in which the ratio of its instantaneous amplitude at one point to that at any other point does not vary with time
wave: (physics) a movement up and down or back and forth
genus metasequoia: genus of deciduous conifers comprising both living and fossil forms; 1 extant species: dawn redwood of China; variously classified as member of Pinaceae or Taxodiaceae