Earlier quoted context omitted.
“Santa Clause” would translate to “holy clause”. There might be such a thing but I think you meant Santa Claus :)
I thought "santa" meant "saint"?
Well, santa is a Spanish word meaning "holy" and saint is a cognate French word meaning the same thing. They descend from Latin sanctus; compare sanctify.
When the prayer goes "holy Mary, mother of god", "holy Mary" is an exact equivalent of "santa María".