adjective

ineffective

ineffective, ineffectual

The medicine was ineffective against the virus.

The medicine was ineffective against the virus.

He was an ineffective leader.

He was an ineffective leader.

ineffective ((against sth.)) not producing the desired result against something The medicine was ineffective against the virus.

Synonyms: useless, futile; Antonyms: effective, potent

From the prefix 'in-' (not) + 'effective' (producing a result). Literally 'not effective'.

Remember that the prefix 'in-' often means 'not'. So, ineffective is simply 'not effective'.

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