Also see definition of "Effectual" in Word Study
Study Dictionary
Effectual
EFFECT; EFFECTUAL [ISBE]
EFFECT; EFFECTUAL - e-fekt', e-fek'-tu-al: In the Old Testament, the Revised Version (British and American) renders "fulfilment" for "effect" in Ezek 12:23 (Hebrew dabhar, "matter"); and in Jer 48:30 "His boastings have wrought nothing" for the vaguer "His lies shall not so effect" of the King James Version. In the King James Version of the New Testament, "make of none effect" occurs repeatedly: as the translation of Greek akuroo, "render void" (Mt 15:6; Mk 7:13); of katargeo, "annul" (Rom 3:3 (the King James Version "make without effect"); Rom 4:14; Gal 3:17); and of kenoo, "make empty" (1 Cor 1:17). the Revised Version (British and American) renders "make of none effect" in Rom 3:3; Gal 3:17; "make void" in the other cases, with no apparent reason for the lack of uniformity. Greek energeo is the opposite in meaning of katargeo above. Its derivative energes, "effective," is rendered "effectual" by English Versions of the Bible in 1 Cor 16:9; Philem 1:6. the Revised Version (British and American) dispenses with "effectual," "effectually," in the other cases where the King James Version has used these words as auxiliary in the translation of energeo or of energeia, "working" (2 Cor 1:6; Gal 2:8; Eph 3:7; 4:16; 1 Thess 2:13; Jas 5:16).F. K. Farr
Also see definition of "Effectual" in Word Study