efficacy

noun

Synonyms and Antonyms of EFFICACY

the power to produce a desired result <questioned the efficacy of the alarms in actually preventing auto theft>

Synonyms edge, effectiveness, effectualness, efficaciousness, efficacity, efficiency, productiveness

Related Words ability, capability, capacity; potency, puissance, strength

Near Antonyms inability, inadequacy, inadequateness, incompetence, incompetency

Antonyms ineffectiveness, ineffectuality, ineffectualness, inefficiency

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