A cottonwood or a cottonwood tree is a kind of tree that grows in North America and has seeds that are covered with hairs that look like cotton.
cottonwood in British English
(ˈkɒtənˌwʊd)
noun
1.
any of several North American poplars, esp Populus deltoides, whose seeds are covered with cottony hairs
2. Also called: tauhinu
a native New Zealand shrub, Cassinia leptophylla, with daisy-like flowers
cottonwood in American English
(ˈkɑtənˌwʊd)
US
noun
1.
any of several poplars that have seeds thickly covered with cottony or silky hairs, esp. a rapidly growing lowland tree (Populus deltoides) of E and central U.S.