True meaning of "por cierto"?

Question

I have always thought of the expression of "por cierto" as meaning "certainly" or "surely." It certainly "looks" that way (for certainly). And even Google Translate gives it that meaning, as well as "by the by" (which is similar to "by the way").Yet when I used this as an answer on another question (since deleted), a native speaker said that it is NEVER used as "surely" or "certainly" in Spain. And the answer was down voted.I'm confused. What's going on? Is "Por cierto" somehow a "false friend" word? Or is this an acceptable translation in Mexico and/or some South American countries, even though this might not be the case in Spain?I am an American who has learned "New World" Spanish.

Answer 1

Por cierto

La expresión "por cierto" (loc. adv.) o "a propósito" se usa para introducir un tema. Ejemplo:

Por cierto, ¿Cuándo vienes a visitarnos?

También "por cierto" tiene un uso formal. Ejemplo:

Tomamos un buen vino, por cierto.

Answer 2

¡Hola! As someone that lived in Spain for 7 years, the only translation of "por cierto" that I can give for Castilian Spanish is "by the way". How it is used in other Spanish-speaking countries, I am not an expert. If I am thinking in English and translating "por" to "for" (only one of that word's meanings") and "cierto" as "sure" (again, only one of the word's meanings), then one would think that it means "for sure". Unfortunately, that's not how languages work. Many common expressions DO have equivalents in Spanish, but they do not translate word for word from English and simply have to be learned from studying the language, reading and speaking to native speakers.