<p><strong>Noun:</strong></p><ul><li>Infirmity</li><li>Weakness</li><li>Senility</li><li>Caducity</li></ul><p><strong>Infirmity:</strong></p><ul><li>The state of being weak or ill, especially due to old age.</li></ul><p><strong>Weakness:</strong></p><ul><li>The quality or state of being weak; lack of strength or firmness.</li></ul><p><strong>Senility:</strong></p><ul><li>The condition of being senile, often marked by a decline in mental or physical abilities associated with old age.</li></ul><p><strong>Caducity:</strong></p><ul><li>The quality of being perishable or transitory.</li><li>The state of being subject to decay or decline, especially related to life.</li></ul>