adj. 25B6; adjective
an effective treatment : SUCCESSFUL, effectual, potent, powerful; helpful, beneficial, advantageous, valuable, useful; formal efficacious.
a more effective argument : CONVINCING, compelling, strong, forceful, potent, weighty, sound, valid; impressive, persuasive, plausible, credible, authoritative; logical, reasonable, lucid, coherent, cogent, eloquent; formal efficacious.
the new law will be effective next week : OPERATIVE, in force, in effect; valid, official, lawful, legal, binding; Law effectual.
Korea was under effective Japanese control : VIRTUAL, practical, essential, actual, implicit, tacit.
weak, invalid, theoretical.