noun A pattern, a way of doing something; especially a pattern of thought, a system of beliefs, a conceptual framework.
Thomas Kuhn's landmark “The Structure of Scientific Revolutions” got people talking about paradigm shifts, to the point the word itself now suggests an incomplete or biased perspective.
noun An example serving as the model for such a pattern; an exceptionally good or prototypical example of a pattern or group.
noun A set of all forms which contain a common element, especially the set of all inflectional forms of a word or a particular grammatical category.
The paradigm of "to sing" is "sing, sang, sung". The verb "to ring" follows the same paradigm.