eficacia

effectiveness

noun eh-fee-KAH-syah Less Common

Origin: From Latin efficacia, from efficax (effective), from efficere (to bring about).

Also means

efficacy

Usage Note

Eficacia means the ability to achieve a desired result (la eficacia del tratamiento = 'the effectiveness of the treatment'). It contrasts with eficiencia (efficiency), which adds the idea of doing it with minimal waste of resources. In pharmaceutical and legal contexts eficacia is often the preferred term over efectividad.

Examples

"Dudaban de la eficacia del nuevo medicamento."

Natural Translation

They doubted the effectiveness of the new medicine.

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