Effectual(a.) Adequate; sufficient to produce a desired effect; as, an effectual writing method; efficient; operative; decisive.
Thesaurus Entries
able, achieving, active, actual, adequate, ascertained, attested, authenticated, authoritative, banausic, behind the scenes, binding, capable, categorically true, causal, causative, certain, certified, charismatic, charming, competent, conclusive, confirmed, consequential, constitutive, corroborated, decisive, demonstrated, determinative, determined, documentary, effective, efficacious, efficient, enchanting, equal to, established, estimable, etiological, factual, feasible, forceful, forcible, formative, fulfilling, functional, go, historical, important, in force, influential, institutive, lawful, legal, magnetic, momentous, not in error, objectively true, occasional, operable, operational, operative, originative, personable, persuasive, pivotal, potent, powerful, practicable, practical, pragmatic, prestigious, productive, proficient, proved, real, realizable, reputable, sound, strong, suasive, substantial, substantiated, sure-enough, telling, toothy, TRUE, true as gospel, truthful, unconfuted, undenied, undoubted, unerroneous, unfallacious, unfalse, unmistaken, unquestionable, unrefuted, up to, useful, valid, validated, veracious, verified, veritable, weighty, winning, workable