provincia

Provincia, provinciae is first declension feminine, and its etymology is genuinely uncertain despite centuries of guessing. What matters is the order of the two senses, because it runs opposite to the English.

The primary meaning is administrative rather than geographical: a provincia is the sphere of responsibility assigned to a magistrate, his job for the year. Only afterwards does it become the territory that job covers, and then a specific territory. When a Roman writer says provincia without qualification he usually means Gallia Narbonensis, the first province across the Alps, which is why the south of France is still called Provence. Keep the abstract sense live: haec provincia mea non est means "this is not my department", not "this is not my province" in any territorial sense.