However I am Dutch i lived for years in France so speak some words.......
The French say ' meekstù ' (English phonetic). The 'ù ' is in fact the short natural ending of the phonetic ' t ' in a sharper way. Sounds like the u from urban but shorter and not like tee.
The bike (velocipède) was invented in France and so was the 'mixte', more a development in the demand of a utility bike in the country-side. Interesting story and still quite actual.
'Mixte' has a more lateral meaning than only the physical 'step through' height of the frame. Social and cultural the bike played an important role in the French style of living and had a big influence in the development of modern cycling.
Will explain in my next message if you are interested in the story.
Au revoir, Bastian