noneffective

/ˌnɑnɪˈfɛktɪv/
adjective
  1. Not producing the desired result or effect; ineffective.
    • The old medicine was noneffective against the new strain of the virus.
    • His noneffective teaching methods left the students confused and frustrated.
    • The company's noneffective marketing campaign failed to attract new customers.
Antonyms
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