Do terms like "pump duty", "compressor duty" or "farm duty" have any basis as a standard? Are these defined terms according to motor manufacturers or rating agencies or electrical standards certifiers? I imagine that the intent is to give some indication of durability. Or ...? Practically, for home shop (intermittent vs an 8-hour work day) would any of these ratings matter? Would they give any indication of bearing quality, windings, etc?

If yes, then where would the standards be found for - for example - a "mill motor" or "metal lathe motor"?