eficaz

effective

adjective eh-fee-KAHS Less Common

Usage Note

Eficaz means 'producing the desired result' and is invariable for gender: un remedio eficaz, una solución eficaz. Its plural is eficaces (the -z changes to -c before -es). Distinguish it from eficiente, which stresses doing something without waste; a treatment can be eficaz (it works) without being eficiente (it may be costly).

Examples

"Esta medicina es muy eficaz."

Natural Translation

This medicine is very effective.

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