adjective
1.
Synonyms: valid , convincing, satisfactory, satisfying, solid, sound, telling
Related Word: compelling, constraining, forceful, forcible, potent, powerful, puissant; inducing, persuasive; justified, well-founded, well-grounded
Contrasted words: ineffective, ineffectual, inefficacious; feeble, forceless, impotent, powerless, weak
2.
Synonyms: well-founded , good, just, justified, well-grounded
Related Word: consequential, influential, momentous, weighty; meaningful, significant