effectual (adjective) effectual: influential; authoritative
Detalii: effective means 'having a (desired) result or effect,' effectual is 'succeeding in producing a desired result or effect,' and efficacious means the same as effectual as well as 'serving as an effective solution or remedy'
Sinonime: creep, flit, glide, go stealthily,
insinuate, lurk, pass quietly, skulk, slide, slink, slip, snake, tiptoe
Antonime: impotent,
incapable,
ineffectual, unproductive,
unsuccessful,
useless,
weak