1
[ adjective ] sufficient to produce a result

Examples

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

Related terms

ineffectual effective

2
[ adjective ] exerting or capable of exerting strong physiological or chemical effects

Examples

"an effectual vaccine"

Related terms

potent

3
[ adjective ] producing or capable of producing an intended result or having a striking effect

Examples

"an air-cooled motor was more effective than a witch's broomstick for rapid transportation"-LewisMumford "effective teaching methods" "effective steps toward peace"

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