A disk in a solid torus is called meridinal if its boundary is a nontrivial curve in (so that it is a meridian). Then a closed subset is called geometrically essential in if intersects every piecewise linear meridinal disk in (Rolfsen 1976, p. 110).
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ReferencesRolfsen, D. Knots and Links. Wilmington, DE: Publish or Perish Press, 1976.
Referenced on Wolfram|AlphaGeometrically Essential
Cite this as:
Weisstein, Eric W. "Geometrically Essential." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/GeometricallyEssential.html