The Collaborative International Dictionary of English v.0.48:

Paradigm \Par"a*digm\, n. [F. paradigme, L. paradigma, fr. Gr.
   ?, fr. ? to show by the side of, to set up as an example;
   para` beside + ? to show. See Para-, and Diction.]
   [1913 Webster]
   1. An example; a model; a pattern. [R.] "The paradigms and
      patterns of all things." --Cudworth.
      [1913 Webster]

   2. (Gram.) An example of a conjugation or declension, showing
      a word in all its different forms of inflection.
      [1913 Webster]

   3. (Rhet.) An illustration, as by a parable or fable.
      [1913 Webster]

   4. (Science) A theory providing a unifying explanation for a
      set of phenomena in some field, which serves to suggest
      methods to test the theory and develop a fuller
      understanding of the topic, and which is considered useful
      until it is be replaced by a newer theory providing more
      accurate explanations or explanations for a wider range of
      phenomena.
      [PJC] Paradigmatic

WordNet (r) 3.0 (2006):

paradigm
    n 1: systematic arrangement of all the inflected forms of a word
    2: a standard or typical example; "he is the prototype of good
       breeding"; "he provided America with an image of the good
       father" [syn: prototype, paradigm, epitome, image]
    3: the class of all items that can be substituted into the same
       position (or slot) in a grammatical sentence (are in
       paradigmatic relation with one another) [syn: substitution
       class, paradigm]
    4: the generally accepted perspective of a particular discipline
       at a given time; "he framed the problem within the
       psychoanalytic paradigm"