A question for French nobility students...?

Question

What is the nobility status of someone who states that they are "a cadet member of the princely family of Rohon in Brittany, ..."? What does it mean to be a "cadet member" of this family?

Answer 1

It means that he/she is another pretentious Fenchman without a pot to stew in!

Answer 2

A cadet is a future officer in the military. The term is often used by uniformed services. The word is recorded in English since 1610, originally for a young son, identical to the French, which is itself derived from Gascon (French Basque dialect of Gascony in southwest France) capdet "captain, chief," in turn from the Late Latin capitellum, the diminitutive of Latin caput "head" (hence also chief). Younger sons from Gascon families apparently were commonly sent to the French court to serve as officers; as a rule non-heirs from the European nobility sought careers in the military or the clergy.

Answer 3

"Cadet"  in French simply means younger than the eldest . In terms of the nobility, only the oldest. gets the title. There is another use of the word in the French nobility which is a "junior" branch of a noble family. Many old French noble houses  had "cadet branches" of which were themselves very powerful.  

So someone saying this could mean they are a a younger member of the family or they might mean they are a member of one of the cadet branches of the family.

The family you ask about is the House of Rohan; later the name used was --and remains--"Rohan-Chabot").  Rohan was one of the greatest families in the Duchy of Brétagne (Brittany) and made several alliances with the reigning house of Brétagne. There was the eldest branch, the vicomtes (later ducs) de Rohan (actually I think the first branch died off sometime before the Revolution)  ; then a well known cadet branch was the Guémené, which became Ducs de Montbazon (and there was at least one cadet branch of that cadet branche as well--Soubise, i think. )  

Another important thing about Rohan is the designation of pair de France (peer of France). This is more exclusive than a peer of the realm in Great Britain, because in France it was not automatically given if you had a certain title, but was an additional honour conferred by the king.

The quote from Wikipedia that Rachelle gave as an example of the use of "cadet"  is correct in that there was indeed a Compagnie des Cadets de Gascogne, made up of cadets of families of Gascogne (and immortalised by Dumas in The Three Musketeers).  However, this would not relate to this princely family of  Brétagne,  which is a not even near Gascogne.