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"Buenos" is a form of "bueno", an adjective which is often translated as "good". "Buenas noches" is a phrase which is often translated as "good evening". Learn more about the difference between "buenas noches" and "buenos" below.
buenas noches(
bweh
-
nahs
noh
-
chehs
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (salutation)
2. (farewell)
bueno(
bweh
-
noh
)An adjective is a word that describes a noun (e.g., the big dog).
1. (beneficial)
a. good
La dieta mediterránea es muy buena para la salud.The Mediterranean diet is very good for your health.
2. (useful)
4. (virtuous)
a. good
Un buen hombre dio su vida por la comunidad anoche.A good man gave his life in the service of this community last night.
5. (delicious)
6. (colloquial) (attractive)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
a. ok
Creo que sería mejor ir al restaurante francés. - Bueno, vayamos.I think it'd be better to go to the French restaurant. - Ok, let's go.