noun: (uncountable) The process of concretizing a general principle or idea by delineating, particularizing, or exemplifying it.
noun: (countable) Something specific which is the result of a process of concretizing a general principle or idea.
noun: (uncountable, medicine, psychology) An inability to generalize or perform abstraction accompanied by excessive concentration on specific details, as in a mental disorder or in cognition by children.