How to Say "demons" in Spanish
The Spanish word for “demons” is “diablos” — B2 level.
English → SpanishB2
NounB2
Supernatural evil beings

Examples
La película trata sobre una lucha entre ángeles y diablos.
The movie is about a fight between angels and devils.
En el carnaval, muchas personas se disfrazan de diablos.
At the carnival, many people dress up as devils.
Según la leyenda, los diablos viven en el infierno.
According to the legend, devils live in hell.
Plural of 'diablo'
This is simply the plural form of 'diablo' (devil). Like most Spanish nouns ending in a vowel, you just add an '-s' to make it plural.
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