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).

# Geometrically Essential

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## References

Rolfsen, D.*Knots and Links.*Wilmington, DE: Publish or Perish Press, 1976.

## Referenced on Wolfram|Alpha

Geometrically Essential## Cite this as:

Weisstein, Eric W. "Geometrically Essential."
From *MathWorld*--A Wolfram Web Resource. https://mathworld.wolfram.com/GeometricallyEssential.html