Lack of strength or power; a state of weakness or inability to exert force or energy.
From Greek 'a-' meaning 'without' plus 'dynamia' relating to strength. This is an alternative form of adynamia, used in medical and scientific contexts to describe powerlessness.
Adynamy is such a philosophical-sounding word that it could almost describe not just physical weakness but also mental exhaustion or creative block—the complete depletion of whatever power you had to move forward.
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