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"Peor" is an adjective which is often translated as "worse", and "mejor" is an adjective which is often translated as "better". Learn more about the difference between "peor" and "mejor" below.
peor()
An adjective is a word that describes a noun (e.g., the big dog).
1. (bad)
a. worse (comparative)
Este sistema operativo es peor que el anterior.This operating system is worse than the previous one.
b. worst (superlative)
Es el peor libro que he leído últimamente.It's the worst book I've read lately.
mejor()
An adjective is a word that describes a noun (e.g., the big dog).
a. better (comparative)
Tu bici nueva es mejor para la montaña que tu bici anterior.Your new bike is better for the mountains than your old bike.
2. (recovered)
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
a. better (comparative)
Me siento mejor que ayer.I feel better than yesterday.
Ella canta mejor que tú.She sings better than you.
4. (preferably)
a. no direct translation
The following examples show ways to translate this word or phrase without using a direct equivalent.
Mejor decírselo, yo creo.I think it would be better to tell them.
Mejor vamos otro día.We'd better go another day.