ancient/ancien regime

What is the difference between ‘ancient regime’ and ‘ancien regime’?

“Ancien Régime” is French, and refers to an old social and political system in France; see

“ancient regime” is a generic English phrase that just means what it says.

Although the two words are clearly cognate, “ancien” in French means something more like “old” or “former” than the English “ancient”.

  1. Hindi and Urdu are cognate languages.
  2. Hindi and Urdu languages are closely akin to one another.
    Are these two sentences OK?

I would use the definite article with (2):
The Hindi and Urdu languages are…

I would also probably not bother with ‘languages’ in (2) if the context made it clear:
Hindi and Urdu are …