Teleology

The study of the ultimate purpose of the design of something in nature.

For example, 'what is the true purpose of the nose?' is a teleological question and, to say that all evolutionary changes occur for a definite purpose is a teleological explanation of evolution.

'Teleology' comes from ancient Greek roots but it (and teleological) did not enter English until the 18th century.

It is a compound of the Greek 'tele-, telos,' meaning 'end or purpose' + the ending 'logos' meaning 'the science or study of' = the study of the ends or purposes.