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"British" is an adjective which is often translated as "británico", and "English" is a noun which is often translated as "el inglés". Learn more about the difference between "British" and "English" below.
British(
brih
-
dihsh
)An adjective is a word that describes a noun (e.g., the big dog).
a. británico 
When you visit London, don't forget to try out the typical British pub!Cuando visites Londres, ¡no te olvides de ir al típico pub británico!
A plural noun indicates that there is more than one person, place, thing, or idea.
a. los británicos (M), las británicas (F)
(m) means that a noun is masculine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The British are famous for their politeness.Los británicos son famosos por su educación.
English(
ihng
-
glihsh
)A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
1. (language)
An adjective is a word that describes a noun (e.g., the big dog).
a. inglés 
Gemma's new boyfriend is English and lives in London.El nuevo novio de Gemma es inglés y vive en Londres.
A plural noun indicates that there is more than one person, place, thing, or idea.
a. los ingleses (M)
(m) means that a noun is masculine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The English are famous for their dry humor.Los ingleses son famosos por su humor seco.