|1.||an apparent change in the position of an object resulting from a change in position of the observer|
|2.||astronomy the angle subtended at a celestial body, esp a star, by the radius of the earth's orbit. Annual or heliocentric parallax is the apparent displacement of a nearby star resulting from its observation from the earth. Diurnal or geocentric parallax results from the observation of a planet, the sun, or the moon from the surface of the earth|
|[C17: via French from New Latin parallaxis, from Greek: change, from parallassein to change, from |
|parallax (pār'ə-lāks') Pronunciation Key
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An apparent shift in the position of an object, such as a star, caused by a change in the observer's position that provides a new line of sight. The parallax of nearby stars caused by observing them from opposite points in Earth's orbit around the Sun is used in estimating the stars' distance from Earth through triangulation.