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see gravitationgravitation,
the attractive force existing between any two particles of matter. The Law of Universal Gravitation

Since the gravitational force is experienced by all matter in the universe, from the largest galaxies down to the smallest particles, it is often called
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The gravitational attraction at the surface of a planet or other celestial body. The quantity g is often referred to simply as “gravity’’ or “the force of gravity’’ of Earth, both of which are incorrect. The force of gravity means the force with which a celestial body attracts an object, that is, the weight of the object. The letter g represents the acceleration caused by the gravitational force and, of course, has the dimensions of acceleration. See Gravitation

McGraw-Hill Concise Encyclopedia of Physics. © 2002 by The McGraw-Hill Companies, Inc.


1. Another name for gravitation.
2. The apparent force of gravitation on an object at or near the surface of a planet, satellite, etc.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006


The gravitational attraction at the surface of a planet or other celestial body.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


1. the force of attraction that moves or tends to move bodies towards the centre of a celestial body, such as the earth or moon
2. the property of being heavy or having weight
3. another name for gravitation
4. lowness in pitch
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005