Elongation is generally defined as the angle between the two planets, or a planet and the sun, or a planet and the moon or the moon and the sun as seen by an observer on the Earth. Venus at elongation suggests the angle between Venus and Sun, and eastern elongation concludes the position of Venus in East of the Sun. Which means the Planet Venus is clearly seen after the sunset in the evening sky in the direction in which the sun sets i.e. west as seen from the Earth.