Main entry: uneffective, ineffective, ineffectual
Definition: not producing an intended effect
Usage: an ineffective teacher; ineffective legislation
Antonyms: effective, effectual, efficacious
Definition: producing or capable of producing an intended result or having a striking effect
Antonyms: toothed
Definition: having teeth especially of a certain number or type; often used in combination
Antonyms: productive
Definition: producing or capable of producing (especially abundantly)
Main entry: ineffective, inefficient
Definition: lacking the ability or skill to perform effectively; inadequate
Usage: an ineffective administration; inefficient workers
Antonyms: competent
Definition: properly or sufficiently qualified or capable or efficient
Antonyms: competent
Definition: legally qualified or sufficient
Main entry: ineffective, ineffectual, unable
Definition: lacking in power or forcefulness
Usage: an ineffectual ruler; like an unable phoenix in hot ashes
Antonyms: stiff, strong, potent
Definition: having a strong physiological or chemical effect
Definition: (of a male) capable of copulation