effectual

英 [ɪ'fektʃʊəl; -tjʊəl] 美[ɪ'fɛktʃʊəl]

• adj. 奏效的；会应验的；有法律效力的

1. sufficient to produce a result;

"a man to whom painting was but another and less effectual way of writing dramas or novels or history"

2. producing or capable of producing an intended result or having a striking effect;

"an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation"-LewisMumford

"effective teaching methods"

"effective steps toward peace"

"made an effective entrance"

"his complaint proved to be effectual in bringing action"

"an efficacious law"

3. exerting or capable of exerting strong physiological or chemical effects;

"an effectual vaccine"