Space extended upward; height; the perpendicular elevation of an object above its foundation, above the ground, or above a given level, or of one object above another; as, the altitude of a mountain, or of a bird above the top of a tree.

Altitude, like elevation, is the distance above sea level. Areas are often considered "high-altitude" if they reach at least 2,400 meters (8,000 feet) into the atmosphere. The most high-altitude point on Earth is Mount Everest, in the Himalayan mountain range on the border of Nepal and the Chinese region of Tibet.

Examples of altitude in a Sentence the air temperature at different altitudes Some visitors find it difficult to adjust to the city's high altitude. The plane lost altitude rapidly.

Answer: The pattern of variation in plant and animal species relative to altitude, in response to vertical differences in climate (especially temperature and precipitation).