first-class object

(programming, languages) An entity that can be constructed at run-time, passed as a parameter, returned from a function, or assigned into a variable.

(programming, languages) An entity that can pass a value as a parameter, can be returned from a subroutine, and can be assigned into a variable. (This is the definition according to Raphael Finkel, who uses the terms of second- and third-class objects.)