Specific feature identified as having a purpose, relating to teleology which studies 'purposes' or 'ends' in general, often related to theistic ideology as used in arguments against evolution, such as the eye is complicated, so has teleonomy, so there's a God.
The contrast between teleonomy and teleology may be construed in etymologic terms. Regarding the former, the suffix -nomy indicates the intentional naming of its subject; whereas the latter, with -ology, implies a study of the subject separate from its observer. To specifically name the end of one's argument within the premises is a fallacy similar to a circular argument.