(1) In Rhinoceros, the interval of the curve parameters where the curve function is defined. The parameter is the variable in the function describing the curve. A curve domain running from zero to one is called a normalised domain.

(2) In Rhinoceros, the intervals of the surface parameters u and v, where the surface function is defined. These parameters are the variables in the function describing the surface. A curve domain running from zero to one in both u and v directions is called a normalised domain.