Not necessarily. In France for example it’s used as an expression even by people who don’t know the math meaning. I know I use it because I sometimes read it in general news articles. It’s not common but definitely used.

The author appears to be Spanish, maybe it’s the same.

Fair enough. A cursory glance at a dictionary corroborates your point - there is clearly a colloquial usage too. I guess I'd never heard its use except in the much more narrow mathematical sense, until now.