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Webster 1913 Edition
Hodograph
Hod′o-graph
,Noun.
[Gr.[GREEK] path +
graph
.] (Math.)
A curve described by the moving extremity of a line the other end of which is fixed, this line being constantly parallel to the direction of motion of, and having its length constantly proportional to the velocity of, a point moving in any path; -used in investigations respecting central forces.