Telos: http://en.wikipedia.org/wiki/Telos_(philosophy)

Teleology: http://en.wikipedia.org/wiki/Teleology

The telos of an acorn is an oak tree. The oak tree might be big or small, warped or straight, well-nourished and healthy or starved and diseased, it might get eaten by a squirrel before ever sprouting, but its potential speaks to an oak tree of some kind, and definitely not a maple, cedar, pine, or any other type of tree. An oak tree.

The telos of a bicycle is somewhat more abstract, because the bicycle itself is not alive, in the way that an acorn is. Instead, and in my opinion, the telos of a bicycle, any bicycle, is the joy experienced by the rider while riding. And while remembering the last ride. And anticipating the next ride. The telos of a bicycle is the joy created by the interaction between the rider and the vehicle, and it is ongoing and ever-evolving.