Noun
(Australia, informal) A tall weed, resembling milkweed, with a ball-shaped seed pod, Gomphocarpus fruticosus (syn. Asclepias fruticosa) and Gomphocarpus physocarpus (syn. Asclepias physocarpa).
Synonym: balloon cotton, swan plant; (in USA) milkweed
Cotton grass (Eriophorum spp)
A shrubby herb (Gossypium thurberi) of southern Arizona and Mexico
Any of the cultivated cottons that have escaped and established themselves in the wild.
Any of several plants of the genera Abutilon and Hibiscus, especially Hibiscus moscheutos
Source: en.wiktionary.org