'barcoo' most likely originates from an Australian Aboriginal language or local placename used by Indigenous people; the exact original word or dialect is uncertain.

'barcoo' was adopted in colonial 19th-century Australia as the name for the Barcoo River and surrounding district, and later came into colloquial English usage to refer generally to remote inland areas ('the Barcoo' or 'out on the Barcoo').

Initially it referred specifically to the river/place name; over time it broadened to an informal term for remote inland/outback regions.