The Collaborative International Dictionary of English v.0.48:

Introspection \In`tro*spec"tion\, n. [Cf. F. introspection.]
   A view of the inside or interior; a looking inward;
   specifically, the act or process of self-examination, or
   inspection of one's own thoughts and feelings; the cognition
   which the mind has of its own acts and states;
   self-consciousness; reflection.
   [1913 Webster]

         I was forced to make an introspection into my own mind.
                                                  --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

introspection
    n 1: the contemplation of your own thoughts and desires and
         conduct [syn: introspection, self-contemplation, self-
         examination]

The Free On-line Dictionary of Computing (30 December 2018):

introspection

    A feature of some programming
   languages that allows a running program to obtain
   information about its own implementation.

   For example, the Lisp function, "symbol-function" takes a
   Lisp symbol and returns the function definition associated
   with that symbol.  Lisp is particularly suited to
   introspection because its source code uses the same
   underlying representation as its data.  Another example is
   Perl's "can" method which returns true if a given
   object's class provides a given method.

   (2010-01-19)