Quaking \Quak"ing\, a. & n. from {Quake}, v. {Quaking aspen} (Bot.), an American species of poplar ({Populus tremuloides}), the leaves of which tremble in the lightest breeze. It much resembles the European aspen. See {Aspen}.
quaking aspen n : Old World aspen with a broad much-branched crown; northwestern Europe and Siberia to North Africa [syn: {European quaking aspen}, {Populus tremula}]