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"Less" is an adjective which is often translated as "menos", and "the least" is a phrase which is often translated as "el menos". Learn more about the difference between "less" and "the least" below.
less()
An adjective is a word that describes a noun (e.g., the big dog).
a. menos
Your neighbor's dog has less hair than yours.El perro de tu vecino tiene menos pelo que el tuyo.
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
the least()
A phrase is a group of words commonly used together (e.g., once upon a time).
a. el menos
I ended up with the least comfortable bed in the house.Terminé con la cama menos confortable de la casa.
a. lo menos
Thanks for helping me move. - Of course. It was the least I could do after you helped me.Gracias por ayudarme con la mudanza. - No hay de qué. Era lo menos que podía hacer después de que tú me ayudaste a mí.
a. el mínimo
Mack is lazy. He does the least work he can.Mack es un perezoso. Hace el mínimo trabajo que puede.
c. el más mínimo
Pablo isn't capable of handling the least bit of adversity.Pablo no es capaz de lidiar con la más mínima adversidad.