grammatical number - What is the plural of Mrs?

If I were speaking of three sisters, young girls, whose family name was "Holmsworth", I might say The Misses Holmsworth.

But if I were speaking collectively of Donald Trump's three wives, the present one and the two previous ones, how would I adopt a similar style? Would it be The Mesdames Trump?

Another question on the site asks a general question about addressing groups of people, but it does not specifically relate to the plural of Mrs.

Answer

According to M-W the form used is the formal but uncommon Mesdames:

It's odd, but there is no common plural form for the titles Mr. and Mrs. in English.

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  Other titles easily become count nouns: Justice Sandra Day O'Connor/Three of the justices recused themselves. Professor Harold Bloom/Ask your professors if you can have extra help. Captain Richard Sharpe/The regiment's captains all gathered for dinner.

  
  


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  But for Mr. and Mrs. there is no common plural form. The plural forms for these titles are only used in formal, official, or otherwise self-conscious writing. They are almost always used when naming people who have already been identified.

  
  


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  The plural for Mr.: Messrs.

  
  


• The plural for Mrs.: Mesdames

For example:

• Messrs. Smith and Jones were named to the company's board at the last general meeting.


• Bush's foreign policy would have been better off examining [...] the informal Republican meetings on Capitol Hill in the late 1990s (in which Messrs. Cheney and Rumsfeld were key participants).

Mesdames:

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  (formal) Used as a title to refer to more than one woman simultaneously:

  
  
  
  
  • prizes were won by Mesdames Carter and Barnes (ODO)
  
  
  
  

As shown in Ngram the usage of "Mesdames" has considerably decreased from the early 20th century.