'barleybird' originates from English, specifically a compound of 'barley' and 'bird'.

'barleybird' appeared as a compound in earlier English dialects and literary usage, used to refer to birds associated with barley fields and later attested chiefly in archaic or regional contexts.

Initially, it simply denoted a bird frequenting barley fields; over time it became an archaic or dialectal label often equated with the skylark.