n (countable) An act of interpreting or explaining what is obscure; a translation; a version; a construction.
n (countable) An act or process of applying general principles or formulae to the explanation of the results obtained in special cases.
n (countable|physics) An approximation that allows aspects of a mathematical theory to be discussed in ordinary language.
n (countable|logic|(w|model theory)) An assignment of a truth value to each propositional symbol of a propositional calculus.