impotencen. 無力、虛弱、無效、陽萎無能力學術名詞性無能：心理學、內分泌學陽痿：動物學、醫學缺精：發生學、植物學陽萎：內分泌學、獸醫學勃起不全：動物學生殖無能：植物學英文釋義the quality of lacking strength or power; being weak and feeblean inability (usually of the male animal) to copulate