Got the dope now: it's a Shimano MT410-B rear hub. I'm not sure about the definition of the part, but the translation I found was retaining pawl. (Freilauf Sperrklinke in German). It works on the principle of a ratchet. Janos says it usually costs about 30 Euros and is easy to replace, no need for a new wheel.
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Great video, Janos! I hope all goes well with your journey home!

Thanks for the suggestion, but I think I’ll stick with my red hat.

You didn't believe me for a split second!

It great to hear that you got out for a walk! I’m glad you have such a great place to stay! I hope your drive home goes well.

I’m so glad you’re feeling better and are writing about it! I can’t believe Janos still came and picked me up with everything going on. Thank you both so much!

I was really impressed at first at what a great shot you got.

Thanks, Kathleen! I am ready for travel again, but not necessarily by bike yet, and tomorrow we start the drive home.

Such kind words, thank you!

Thanks for the good wishes, Tricia!

Finally getting back to you, Jacquie. The part is in the Shimano MT410-B rear hub. I'm not sure about the definition of the part, but the translation I found was retaining pawl. (Freilauf Sperrklinke in German). It works on the principle of a ratchet.

Good luck! Janos now tells me I had completely misunderstood. The pedals turned freely in both directions but didn't turn the wheels. (I swear he said something else at the time.) Anyway, he is now off flying his drone and when I asked last night, he said he didn't know what kind of hub but would look today. Our bikes, which our hosts carried in for us, are somewhere off in the courtyard, I haven't seen them since our arrival at our B&B. If it's pertinent information, I hope we can get it to you in time.

Thanks Suzanne! Based on your preliminary info, we are waiting right now on bike shops to open here in Orleans. But we expect it will be like your doctor thing - not possible to get immediate and good service. We would then strike off tomorrow toward Chartres, and hope the thing does not lock up in the middle of nowhere!

How sorry we are to read this. Such a nightmare for you. We are delighted things are trending in the right direction, but what a debilitating and frightening experience. You must have felt so vulnerable. So glad you had such a good support system, but where were the doctors when you really needed one? Take it easy and continue to get your strength back.

I went to bed dreaming of your tale, Suzanne. Even though we do not personally know each other at all, your wonderful photos, blogs and information are what started me on the cycle blaze site in the first place a year ago. Your tales of this ordeal are not too long at all, except the “I am all better” has yet to be read. It will be very interesting to finally discover what this actually was! Still praying nothing really serious; you have been through enough already…