Reverse Dictionary: EFFECTIVE

ADJECTIVES
► AFFECTUOUS influential, effective, successful → 1674 obs.
► CROWNED unfailingly effective, perfect; also, completed, consummated → 1405
► DANGEROUS extremely effective or impressive → 1984 US sl.
► DEEDFUL full of action or deeds, effective → 1842
► DYNAMIC active, potent, energetic, effective, forceful → 1856
► DYNAMIZED rendered more dynamic or effective; energized, invigorated → 1920
► EFFECTUOUS efficacious, effective → c1400 obs.
► EFFICABLE efficacious, effective → 1607 obs.
► EFFICACE that produces the intended or appropriate effect; effective → a1500 obs.
► EFFICACIOUS that produces the intended or appropriate effect; effective → 1528
► PERFICIENT accomplishing or achieving something; effective → 1659
► PERFORMANT performing or operating well; functioning at a high or sophisticated level; effective → 1977
► PUNCHY full of punch or vigour; forceful; being or appearing vigorously effective → 20C sl.
► SICKER certain of its effect; effective, sure → 1338
► SUBSTANTIOUS weighty, important; solid, firm; effective → 1483 chiefly Sc. obs.
► SUFFISANT satisfactory in quality or efficacy; effective → 1340 obs.

ADVERBS
► DEEDFULLY actively, effectively → 1615
► EFFECTUOUSLY effectively, with powerful effect → a1400 obs.
► EFFICACIOUSLY effectively → 1647
► FELLENLY vigorously; effectively, extremely well → 1882 Sc.
► PUNCHILY forcefully, effectively; vigorously → 1934

NOUNS
► ACE IN THE HOLE, AN something effective in reserve 
► EFFICACE efficacy, effectiveness → a1225 obs.
► EFFICACIOUSNESS effectiveness → 1630
► EFFICACITY effectiveness, efficacy → 1430-50
► EFFICIENCE effectiveness, efficacy → 1865 arch.
► SWINGER something very big or excellent; something forcible or effective → 1599 colloq.

NOUNS – PERSON
► HALER ► HAYLER one who works or does anything energetically and effectively → 1870 Eng. dial.
► WORLD-BEATER a very effective person; a winner; a champion → 1893 sl.

VERBS
► COOK ON THE FRONT BURNER to do well, to work effectively → 1945 Amer. dial.
► DO THE BUSINESS to accomplish a task; later, to be successful or effective, to do well → 1603
► EFFECTIVATE to render effective; to effectuate → 1717 Sc.
► FADE to lose or cause to lose power and effectiveness → 1450
► FILL THE BILL to be very effective, or competent → c1885