In mathematics, the flatness (symbol: ) of a surface is the degree to which it approximates a mathematical plane. The term is often generalized for higher-dimensional manifolds to describe the degree to which they approximate the Euclidean space of the same dimensionality. (See curvature.)[1]

Flatness in homological algebra and algebraic geometry means, of an object in an abelian category, that is an exact functor. See flat module or, for more generality, flat morphism.[2]

Character encodings

Character information
Unicode name FLATNESS
Encodings decimal hex
Unicode 9189 U+23E5
UTF-8 226 143 165 E2 8F A5
Numeric character reference ⏥ ⏥

See also


  1. ^ Committee 117, A. C. I. (November 3, 2006). Specifications for Tolerances for Concrete Construction and Materials and Commentary. American Concrete Institute. ISBN 9780870312212 – via Google Books.((cite book)): CS1 maint: numeric names: authors list (link)
  2. ^ Ballast, David Kent (March 16, 2007). Handbook of Construction Tolerances. John Wiley & Sons. ISBN 9780471931515 – via Google Books.