- Effective Ef*fect"ive, a. [L. effectivus: cf. F. effectif.]
Having the power to produce an effect or effects; producing a
decided or decisive effect; efficient; serviceable;
operative; as, an effective force, remedy, speech; the
effective men in a regiment.
They are not effective of anything, nor leave no work behind them. --Bacon. [1913 Webster]
The Collaborative International Dictionary of English. 2000.