Why do so many Hispanic last names end with z?

[Dr.Drake]

@Acsenray

Any diminutive or hypocorism used as a patronymic is a patronymic, the same way that a completely unaltered given name that is used as a patronymic is also a patronymic.

Could you define patronymic then, please? There is already some confusion in this thread (and in my head). If I read you right, it’s

• Any surname with an element “son / daughter / child of” + father / male ancestor’s given name

• Any surname based on the father / male ancestor’s given name + possessive¹

• Any surname based on the father / male ancestor’s given name

What about

• Any surname based on the father / male ancestor’s nickname (Short, Brown)?

¹Incidentally the explanation for the Italian names in -i above: fossilized genitive back when Latin / Old Italian nouns had cases.

ETA: This is something of a cross-posting, since I didn’t see your definition when I hit “post.” I’m still curious about whether nicknames would count, though.

[Bambi_Hassenpfeffer]

@bordelond

Maybe, but I wasn’t necessarily thinking that patronymic -ez was Latin-derived. Could have been borrowed from Germanic, or could be holdover from a substrate language.

There’s also the Serbian/Bosnian/Croatian ić (roughly “eech”), Russian -ovich, -yevich, -yich, and Romanian -escu, which seem related to me as well – to each other and to -ez. Of course, I’m probably wrong .

[Mississippienne]

@Gyrate

Names beginning with “Fitz-” (Fitzpatrick, Fitzgerald, etc) are also “son of” names. I vaguely recall reading that bastard sons of monarchs were saddled with these in particular.

Oft-repeated but inaccurate. The “Fitz” names (Fitzgerald, Fitzhenry, etc.) come from the Norman French fils de, “son of”, and have no particular connetation of illegitimacy.

The confusion comes thanks to the surname Fitzroy, which was, indeed, the name given to illegitimate sons of kings (fils de roi, “son of the king”).

[Gyrate]

@Mississippienne

Oft-repeated but inaccurate. The “Fitz” names (Fitzgerald, Fitzhenry, etc.) come from the Norman French fils de, “son of”, and have no particular connetation of illegitimacy.

The confusion comes thanks to the surname Fitzroy, which was, indeed, the name given to illegitimate sons of kings (fils de roi, “son of the king”).

Vaguely misremembered, then. Thanks for the correction.

[Hypnagogic_Jerk]

@Captain_Amazing

Not a good one. Wiktionary says so.

Sancho - Wiktionary, the free dictionary

as does Wikiname, which pretty stupidly says in one sentence that the name is of Latin origin and then in the next that it “may be of Basque origin.”

I guess it could be both: a Basque name that was then identified with the Latin Sanctus. Isn’t Diego, while generally considered a Hispanic form of Jacob, also derived from a name from a substratum language?

[Polycarp]

@Mississippienne

Oft-repeated but inaccurate. The “Fitz” names (Fitzgerald, Fitzhenry, etc.) come from the Norman French fils de, “son of”, and have no particular connetation of illegitimacy.

The confusion comes thanks to the surname Fitzroy, which was, indeed, the name given to illegitimate sons of kings (fils de roi, “son of the king”).

There were also a couple of mistresses of monarchs/heirs (George III’s sons IIRC) whose surnames were Fitzsomething, which addeed to the "king’s bastard) meme.

[Polycarp]

@Hypnagogic_Jerk

I guess it could be both: a Basque name that was then identified with the Latin Sanctus. Isn’t Diego, while generally considered a Hispanic form of Jacob, also derived from a name from a substratum language?

Nope – it’s from Di Iago, which in turn is from Iacobus.

[Hypnagogic_Jerk]

Okay, but what I’m suggesting is that it comes from both, i.e. that it is a variant of Iacobus, but that its actual form was influenced by another preexisting name. Or am I thinking of another Hispanic name? I remember hearing something similar to that here on the SDMB.