effectual
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
Synonyms: effective efficacious
Examples:

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

Related terms: ineffective hard-hitting impelling impressive hard-hitting rough-and-ready powerful useful efficient potent efficacious effectiveness
Similar spelling:   effectually
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  effect
  effectuate
  effectuation
  effects
  effectivity
  effectively
  effector
  effecter
  effected
  effective