Not producing the desired result or having little to no effect. Lacking the power to accomplish a purpose or achieve success.
From Latin 'in-' (not) + 'effectivus' (producing results), from 'efficere' (to accomplish). The word entered English in the 17th century, combining the negative prefix with 'effective' to denote absence of desired outcomes.
The word 'ineffective' is fascinating because it reveals our human obsession with results and productivity - we needed a specific word just to describe when things don't work as intended. Interestingly, calling something 'ineffective' often implies there was an expectation or standard it failed to meet, making it inherently comparative.
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