Engels [adj]Spaans [adj] ▶effective [adj] This medicine is effective against allergies. ▶eficaz [adj] Este medicamento es eficaz contra las alergias. ▶efficacious [adj] The doctor chose an efficacious treatment for her condition. ▶eficaz [adj] El médico eligió un tratamiento eficaz para su afección. ▶efficient [adj] ▶eficaz [adj]