ANT: Origin, cause.
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KEY: Effective.
SYN: Powerful, conducive, operative, cogent, telling, able, potent, talented, efficacious, efficient, serviceable, effectual.
ANT: Weak, ineffective, inconducive, inoperative, futile, nugatory.
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KEY: Effectuate.
SYN: Produce, ensure, secure, stabilitate, compass, complete, establish.
ANT: Prevent, hinder, nullify, defeat, nip, blight, strangle, stifle, abolish.
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