An object of a concrete category is finitely generated if it is a quotient object of some free object in , where is free on a finite set. (We probably want ‘quotient object’ here to be interpreted in the sense of a regular epimorphism from to , although perhaps we explicitly want it to be the quotient of a congruence on .)
The object is finitely presented if it is the quotient of a congruence such that is also free on a finite set. (Or maybe we don't demand that this is a congruence but accept any coequaliser of this form?)
See discussion at finitely presentable object more a more abstract version of these.