| Noun | 1. | cottonwood - any of several North American trees of the genus Populus having a tuft of cottony hairs on the seedpoplar tree, poplar - any of numerous trees of north temperate regions having light soft wood and flowers borne in catkins Eastern cottonwood, necklace poplar, Populus deltoides - a common poplar of eastern and central United States; cultivated in United States for its rapid growth and luxuriant foliage and in Europe for timber Populus trichocarpa, Western balsam poplar, black cottonwood - cottonwood of western North America with dark green leaves shining above and rusty or silvery beneath black cottonwood, downy poplar, Populus heterophylla, swamp cottonwood, swamp poplar - North American poplar with large rounded scalloped leaves and brownish bark and wood |
| 2. | cottonwood - American basswood of the Allegheny regionlinden tree, basswood, lime tree, linden, lime - any of various deciduous trees of the genus Tilia with heart-shaped leaves and drooping cymose clusters of yellowish often fragrant flowers; several yield valuable timber |