efficacy

nounCommon GRE wordMore E words

the power to produce a desired result or effect

In a sentence

Efficacy in a sentence

Here is an example sentence showing efficacy in a sentence.

Researchers questioned the efficacy of the unproven treatment.

Synonyms

effectivenesspotencyusefulness

Antonyms

ineffectivenessuselessnessimpotence

Keep going

to gradually decline, recede, or diminish

overflowing enthusiasm and liveliness

the quality of overflowing, bubbling enthusiasm

overflowing with cheerful enthusiasm and high spirits

deviating from conventional or accepted behavior in odd ways

a level or rank within an organization, profession, or society

drawing from a wide and diverse range of sources or styles

to deprive of importance or overshadow by being superior

Common questions

Efficacy (noun) means the power to produce a desired result or effect

Here is efficacy used in an example sentence: "Researchers questioned the efficacy of the unproven treatment."

Common synonyms for efficacy include effectiveness, potency, usefulness.

Antonyms of efficacy include ineffectiveness, uselessness, impotence.

Efficacy is a GRE-level vocabulary word worth knowing for the Verbal section.

Vocabulary sticks when you meet it in real sentences. Practise these words inside text completion and sentence equivalence questions.