La·gran·gi·an point (lə-grānjē-ən)
Astronomy Any of five points in the orbital plane of two bodies, one of which is much larger than the other, at which a third, even smaller body will remain in gravitational equilibrium. Bodies located at Lagrangian points appear stationary with respect to the larger two bodies. Also called Lagrange point.
[After Comte Joseph Louis LAGRANGE.]
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