I've just heard
your sister is waiting on you
with the meaning of wait for (as in wait for the bus).
Up to now I had only encountered wait on with the meaning of attend to / serve.
Is this use of wait on instead of wait for widely spread in the English speaking world or more specific to certain geographical areas?
In the sentence I'm quoting above, and without further context, could there be any ambiguity as to the meaning?
