What Does The Spanish Word 'Cada Mia' Mean?

Cada=Each.
Cara=Face, or dear.
Casa=House
Mia=Mine. Feminine form.
Dia=Day.

Cada mia = can just mean, "each of mine" in English. Or "All mine", "every bit is mine", even. Where whatever is being referred to has to be a feminine noun (hence the A at the end of Mia). So it could be a possessive phrase used between lovers, like "you are mine". Well, really it's a phrase a man would use for a woman because of the feminine "mia" ending. Also likely it's a typo, though.

Often "Cada mia" is a typo, for the expression "Cada Dia" - which means "every day" in English. I can find a lot of typos on the Internet like that.

And then there's Casa Mia, which would be "My House", and so sometimes "Cada Mia" is a typo for that.

Cara Mia = that would mean "My face" in English, OR "My dear". So Cada Mia could be a mistype for Cara Mia-- "My beloved one".

In fact 'Cada Mia' does not have any kind of meaning in Spanish. 'Cada" means 'Each'. 'Mia' is the feminine of 'Mine'. So the most probable meaning of 'Cada Mia' would be "Each mine' and obviously it's incorrect grammatically.
Maybe you have misunderstood the words or the language: In Italian 'cara mia' would mean 'my dear'.

The name Mia is a latin name and it means mine and it started in italy

Van