1. Lacking physical strength or vigor; weak.
2. Lacking in power, as to act effectively; helpless: "Technology without morality is barbarous; morality without technology is impotent" (Freeman J. Dyson).
3. Incapable of sexual intercourse because of an inability to achieve or sustain an erection.
4. Obsolete Lacking self-restraint.
[Middle English, from Old French, from Latin impotēns, impotent- : in-, not; see IN-1 + potēns, potent; see POTENT.]
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