n. The center of a mass; often specifically, the point at which the gravitational forces exerted by two objects are equal
n. The centroid, the geometric center of a plane figure
the GNU version of the Collaborative International Dictionary of English
n. the point representing the mean position of the matter in a body.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. (astronomy) the common center of mass around which two or more bodies revolve
Word Usage
"Stars in pairs both orbit around a point in space called a barycenter, and researchers at times saw these orbits were slightly off, suggesting the presence of a planet tugging at both stars."