rabbitbrushEnglishOxford New American Dictionaryrabbitbrush /ˈrabitˌbrəSH , ˈræbɪtˌbrəʃ / (also rabbitbush /-ˌbo͝oSH/) ▸ noun a shrub of the daisy family that bears clusters of pungent small yellow flowers, native to North America, especially the western US. Chrysothamnus nauseosus, family Compositae.