Here is a thread in which two Mexicans confirm that usage.
In another thread, zumac (Mexican) said, "In Mexico, curb would be 'cuneta.'"
I actually don’t think that there is one best go to word to use. Because one can think it’s the best “go to”word, and you could use it with a Spanish-speaker, but their best “go to”word might be something different, and they might not know what you’re talking about, or think it’s something else… when I say go to word, I’m referring to what OtroLecho mentioned, But also, combined with what you mentioned here, realizing that a true definition of this for many Spanish-speakers remains very nebulous.
That is why, if you definitely just need to focus on the meaning, and not necessarily a specific term, la orilla/el borde de la banqueta/acera may universally get the job done… Yes, it sounds a bit unorthodox… but you sure would avoid someone saying ¿Qué es eso? …. Because, don’t get me wrong, all of the specific terms that we heard are correct, not so much Cuneta, but anyhow… If you use any of them, you take the gamble of the person not really knowing… this term is just more nebulous in the Spanish language. In English, if you say curb, there is no debate on how to say this, everyone knows that a curb is a curb. This is just the nature of how this term is understood and used differently in the Spanish-speaking world. I interpreted for a Spanish speaker once, and we were referring to the ditch along the side of the road, which is a “cuneta”, but to her, it was “el hoyo.” My point, not only are there many precise words depending on the region, people ALSO have their own reality of what the word is to them, and beg to differ. Cunetas to me slope down, and are not an upright edge like that one picture in this thread, which is specifically what I’m referring to.
Maybe cuneta used as gutter is what that link was getting it… Where the water flows along side flush with the curb? I can maybe see that is an acceptable use of cuneta as curb…but not really. However, that is not even the raised edge. Curb is all about the “raised” edge, like the picture in the thread that was provided. Or, at least referring to the edge of the sidewalk, as its definition is stated on dictionary.com. Click images For the Cuneta entry on word reference. It is either a ditch that slopes down at the side of the road, or a cement curb that slopes down, as to help water flow. Sort of like a curb, yes, definitely, because it does have a raised edge, but the big difference is, that after the raised edge, it has a slope downward to help water flow(gutter)… I think the term could’ve been generically used for any kind of curb, but it’s not entirely accurate to the kind of curb from the picture that was provided in the thread, which does not slope down, as to have water flow as a gutter. And also, it is also a continual ditch along the side of the road-another way of using cuneta.
