Elimination of Imaginaries

A property of a theory that every definable equivalence class (an 'imaginary') can be coded by a tuple of real elements (elements of the home sorts), so that every imaginary has a canonical parameter in the real sorts and no extra imaginary sorts are needed.

A property of a theory saying that every definable set (with parameters) admits a canonical parameter (an 'imaginary' element) in the home sorts or in a definable expansion, so definable quotients are represented by real elements or named sorts.