Definition of blue bush in US English:

blue bush

noun

  • Any of several shrubs having leaves of a bluish colour; specifically (a) the South African shrub Diospyros lycioides (family Ebenaceae); (b) any of several plants native to arid areas of Australia, especially those of the Australian genus Maireana (family Amaranthaceae), and the perennial goosefoot Chenopodium auricomum.

Origin

Early 19th century; earliest use found in Edinburgh New Philosophical Journal. From blue + bush.

Pronunciation

blue bush

/ˈbluː ˌbʊʃ/