4 days ago · Efficient most often describes what is capable of producing desired results without wasting materials, time, or energy. While the word can be applied to both people and things, it is far more … The adjective effective describes things that are adequate to accomplish a purpose, or that produce the intended or expected result. But effective isn’t quite the same as effectual, efficacious, or efficient! successful or achieving the results that you want: 2. (used about a treatment or drug) working…. Definition of effective adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. Effective and efficient are often confused, but they have slightly different meanings. If you are effective, you do a job properly; if you are efficient, you do it quickly and easily. Apr 26, 2026 · Adjective effective (comparative more effective, superlative most effective) Having the power to produce a required effect or effects. Effective, effectual, efficacious, efficient refer to that which is able to produce a (desired) effect. There are 17 meanings listed in OED's entry for the word effective, five of which are labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.
