It recently occurred to me that the Spanish nuez can be translated to English as both "walnut" and "pecan." Is the same word really used for both types of nuts? How would you specify which nut you're talking about when the difference is important (say, in a recipe)?
At least in Colombia one usually would say nuez, generically, if the context doesn't require the specific kind of nut; in the case of a recipe (or in any other context in which the difference matters) we, of course, have (and use) different names:
And perhaps more that I cannot remember right now.
Hope it helps.
PECANS: never heard of it as Nuez China, but it could be a regionalism. A friend that has a bakery orders them in Mexico as Nuez Pecana.
WALNUTS: Nuez de Castilla, but I've always referred to them as just "nuez" I just learned that in Peru is called Nuez de Nogal, makes sense since in Mexico we have a dish called Chiles en Nogada, The Nogada is made with walnuts! Makes Perfect Sense!
NUTMEG: Nuez Moscada, in Mexico is really hard to find in it's natural shape, often found in powder in the spice aisle.
CASHEWS: Nuez de la India
MACADAMIAS: Nuez de Macadamia
PINE NUTS: Piñones
BRAZILIAN NUT: (Brace yourself) I knew them as "Talón de negro" which literally means "Black man's heel". Obviously it is very politically incorrect, so I'm guessing we just take the literal translation "Nuez de Brasil".
@jrdioko One must differentiate between the general case and the particular cases. @Gonzalo Medina has already pointed you several particular cases, but I'd like to address the general case.
The English word "nut" refers to all oily seeds produced by some wood trees and palm trees. It is the same for the Spanish word "nuez". When you refer to a particular case, you qualify the word making it narrower in meaning. In some cases you have a different word to refer to that particular case, e.g., "hazelnut/avellana". But your original premise is incorrect. "Nuez" does not mean "walnut" nor "pecan" nor it is a synonym of both either.
In the spanish of Peru, a walnut is known as a Nuez de Nogal and a pecan is known as a Pecana. Brazil nuts are Castanas (the n should have a cidilla) , peanuts which are originally from there are Mani or Manies. So your recipe would call for Nogales or Pecanas.