A triangle that is equal to its polar triangle with respect to a given conic is said to be self-polar with respect to that conic. Any triangle is self-polar with respect to the polar circle and Stammler hyperbola.
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This entry contributed by Floor van Lamoen
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van Lamoen, Floor. "Self-Polar Triangle." From MathWorld--A Wolfram Resource, created by Eric W. Weisstein. https://mathworld.wolfram.com/Self-PolarTriangle.html