#elevation  distance of something above a reference point
  supertype:  #distance  the property created by the space between two objects or points
  subtype:  #isometry  equality of elevation above sea level
  subtype:  #altitude.elevation__height  elevation especially above sea level or above the earth's surface
     subtype:  #level  height above ground: "the water reached ankle level"; "the pictures were at the same level"
     subtype:  #lowest_layer_of_clouds__ceiling  (meteorology) altitude of the lowest layer of clouds
     subtype:  #plane_maximum_altitude__planemaximumaltitude__ceiling  maximum altitude at which a plane can fly (under specified conditions)
        subtype:  #absolute_ceiling  the maximum altitude at which an air plane can maintain horizontal flight
        subtype:  #combat_ceiling__service_ceiling__serviceceiling  altitude above which a plane cannot climb faster than a given rate
  subtype:  #ground_level__grade  the height of the ground on which something stands: "the base of the tower was below grade"
  subtype:  #water_level  the level of the surface of a body of water
     subtype:  #sea_level__sealevel  level of the ocean's surface esp that halfway between mean high and low tide; used as a standard in reckoning land elevation or sea depth

No statement uses or specializes #elevation; click here to add one.