Aut *celer* aut *vēlōx*?

Question

Celer and vēlōx are often treated as synonymous. I feel certain that I learned the technical distinction between them once: that celer was potential speed, while vēlōx was actual speed. So Usain Bolt sitting on the couch would be celer (he's capable of moving very quickly), but not vēlōx (he isn't moving quickly at the moment). Conversely, stones being whipped around in a hurricane would be vēlōx (they're going really fast) but not celer (it's not their natural state).

However, neither Döderlein nor L&S makes any mention of this. Is my memory deceiving me? Or have others heard about this distinction as well?

Answer 1

celer was potential speed (…) but not vēlōx

A counterexample can be found in Cæsar's Commentarii de bello Gallico:

Genus hoc erat pugnae, quo se Germani exercuerant: equitum milia erant VI, totidem numero pedites velocissimi ac fortissimi, quos ex omni copia singuli singulos suae salutis causa delegerant (…)

Commentarii de bello Gallico, I, 48

However, celer and velox haven't exactly the same meaning, as explained in this book I've just found:

In Dumesnil, Latin Synonyms with Their Different Significations and Examples Taken from the Best Latin Authors, 1809