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"Rapid" is an adjective which is often translated as "rápido", and "fast" is an adjective which is also often translated as "rápido". Learn more about the difference between "rapid" and "fast" below.
rapid(
rah
-
pihd
)An adjective is a word that describes a noun (e.g., the big dog).
1. (quick)
a. rápido
We can't kayak in the river because the current is too rapid.No podemos hacer kayak en el río porque la corriente es demasiado rápida.
b. veloz
Adding an enzyme to the vial will make for a much more rapid chemical reaction.Añadir una enzima al frasco hará que la reacción química sea mucho más veloz.
rapids
A plural noun indicates that there is more than one person, place, thing, or idea.
a. los rápidos (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).
During our vacation, we went rafting on the whitewater rapids.Durante las vacaciones, fuimos a hacer rafting por rápidos de aguas bravas.
fast(
fahst
)An adjective is a word that describes a noun (e.g., the big dog).
1. (quick)
3. (firm)
b. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
I made the boat fast to a dock cleat.Amarré el barco a una cornamusa.
She jumped down from her horse, and tied the rope fast to a tree.Saltó de su caballo, y ató bien la cuerda a un árbol.
a. inalterable
You can use bleach when washing this sweatshirt, because the color is fast.Se puede usar blanqueador al lavar esta sudadera, porque el color es inalterable.
a. disoluto
The sailors went looking for fast girls.Los marineros salieron en busca de chicas disolutas.
6. (film)
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
8. (quickly)
a. rápidamente
They moved really fast, so we weren't able to follow them.Se movieron muy rápidamente, así que no los pudimos seguir.
b. rápido
It happened so fast that I hardly remember it.Sucedió tan rápido que apenas lo puedo recordar.
9. (firmly)
10. (soundly)
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
