Hypertext Webster Gateway: "Acnode"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Acnode \Ac"node\, n. [L. acus needle + E. node.] (Geom.)
An isolated point not upon a curve, but whose co["o]rdinates
satisfy the equation of the curve so that it is considered as
belonging to the curve.
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