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"Eficaz" is an adjective which is often translated as "effective", and "efectivo" is an adjective which is also often translated as "effective". Learn more about the difference between "eficaz" and "efectivo" below.
eficaz(
eh
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fee
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kahs
)An adjective is a word that describes a noun (e.g., the big dog).
a. effective
Los investigadores esperan descubrir un tratamiento más eficaz para la diabetes.Researchers hope to discover a more effective treatment for diabetes.
a. efficient
Estamos desarrollando un proceso de producción de electricidad más eficaz.We are developing a more efficient process of producing electricity.
efectivo, el efectivo(
eh
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fehk
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tee
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boh
)An adjective is a word that describes a noun (e.g., the big dog).
a. effective
La vacuna tarda unos días en ser efectiva.The vaccine takes a few days to become effective.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
los efectivos
A plural noun indicates that there is more than one person, place, thing, or idea.
4. (military)
a. forces
El país aumentó el número de efectivos militares en la zona.The country increased the number of military forces in the area.
