<p><strong>Noun</strong></p><ul><li>any of various poplars, as Populus tremula, of Europe, and P. tremuloides quaking aspen or P. alba white aspen, of America, having soft wood and alternate ovate leaves that tremble in the slightest breeze</li></ul><p><strong>Adjective</strong></p><ul><li>of or relating to the aspen</li><li>trembling or quivering, like the leaves of the aspen</li></ul>