CAUSE
There could be multiple reasons for this error.
jQuery DataTables library is missing.
jQuery library is loaded after jQuery DataTables.
Multiple versions of jQuery library is loaded.
SOLUTION
Include only one version of jQuery library version 1.7 or newer before jQuery DataTables.
For example:
See jQuery DataTables: Common JavaScript console errors for more information on this and other common console errors.
This worked for me. But make sure to load the jquery.js before the preferred dataTable.js file. Cheers!