One word for daughter's father in law?

Answer 1

I too am looking for a term in English.

Hebrew (and Yiddish) have terms.

The two sets of parents of a married couple are M'CHUTANIM.

(M'CHUTANIM is also used for any in-law.)

Each father is a M'CHUTAN. Each mother is a M'CHUTENET.

The root of these words is related to CHATUNA which means wedding.

L'HITCHATEIN is to get married.

A groom is called a CHATAN.

That too is the term for son-in-law.

A father-in-law is a CHOTEIN.

Yiddish has variations on these words.

It is unrealistic to expect that the lexicons of different languages will have terms that exactly correspond. As languages evolve so do vocabularies - if a word doesn't function effectively it is changed or drops out of use. "Mother-in-law" has evolved in English to distinguish between a person's natural mother and the mother of their spouse. This distinction is most often used when speaking to a third person but not so often when speaking directly to the Mother-in-law.

It is quite usual over time for English families to refer to both sets of parents by the terms 'mother' and 'father' and their derivatives - just as you have described in Yiddish. However, a shorthand may develop with someone referring to their natural mother as Mum and their mother-in-law as "mother". In much the same way as terms for grandparents are varied to distinguish between the mother's and father's parents - perhaps Grandma and Grandpa for one set and Nanna and Pops for another. This works in reverse to with in-laws referring to son-in-law as 'son'.

Quite often a son- or daughter-in-law will refer to the spouse's mother by the mother's own first name.

Of course different families manifest different degrees of formality and what is considered appropriate within one family may be frowned upon in another.

Answer 2

The one I thought of and then Google-checked is co-father-in-law. It makes sense and there are citations of its historical usage if you simply Google that three-hyphen word. Of course, this works only for the co-father-in-laws and co-mother-in-laws.

Answer 3

Man.

There is no description of the relationship that is one word. You can say, "He is the father of my daughter-in-law." or "He is my son's father-in-law."