noun (used with a singular verb)
the science dealing with the paths of space vehicles.
Origin of astrodynamics
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
(functioning as singular) the study of the motion of natural and artificial bodies in space
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The dynamics of natural and artificial bodies in outer space.
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