éifeachtúlacht

== Irish == === Etymology === From éifeachtúil (“effectual”) +‎ -acht (abstract suffix). === Noun === éifeachtúlacht f (genitive singular éifeachtúlachta) efficaciousness, efficacy efficiency ==== Declension ==== ==== Synonyms ==== (efficiency): éifeachtacht ==== Antonyms ==== neamhéifeachtúlacht === Mutation === === References === "efficaciousness, efficacy" in English-Irish Dictionary, An Gúm, 1959, by Tomás de Bhaldraithe.