effectual

sufficient to produce a result

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

producing or capable of producing an intended result or having a striking effect

• “an air-cooled motor was more effective than a witch”
• “-LewisMumford;”
• “;”
• “;”
• “;”
• “;”

exerting or capable of exerting strong physiological or chemical effects

• “an effectual vaccine”