Orientable Surface
A Regular Surface 
is called orientable if each Tangent Space 
has a ComplexStructure 
such that 
is a continuous function.
References
Gray, A. Modern Differential Geometry of Curves and Surfaces. Boca Raton, FL: CRC Press, p. 230, 1993.
- Number Theory
- Number Triangle
- Number Wall
- Numerator
- Numerical Derivative
- Numerical Integration
- Numeric Function
- Numerology
- NURBS Curve
- NURBS Surface
- Nyquist Frequency
- Nyquist Sampling
- Néron-Severi Group
- Nöther
- Obelus
- Object
- Oblateness
- Oblate Spheroid
- Oblate Spheroidal Coordinates
- Oblate Spheroidal Wave Function
- Oblate Spheroid Geodesic
- Oblique Angle
- Oblong Number
- Obstruction
- Obtuse Angle