The species was first formally described in 1839 by English botanist John Lindley in A sketch of the vegetation of the Swan River colony.

Adenanthos barbiger grows as an upright or spreading small shrub, up to 1 m (3 ft) in height, often with many stems arising from an underground lignotuber.

[2][3] This species was first published under the name Adenanthos barbigera by John Lindley in his 1839 A Sketch of the Vegetation of the Swan River Colony.

[2] In 1870, George Bentham published the first infrageneric arrangement of Adenanthos in Volume 5 of his landmark Flora Australiensis.

[6] In 1921, Carl Hansen Ostenfeld published Adenanthos intermedia (now A. intermedius), based on specimens found at Yallingup with leaf shape intermediate between those of A. barbiger and those of A. obovata.

This was rejected in 1978 by Ernest Charles Nelson, who argued that leaf shape is inappropriate grounds for erecting a new species in this context, and that, in terms of systematically important characteristics, A. intermedius is indistinguishable from A. barbiger.

Eurylaema in Ernest Charles Nelson's 1978 revision of Adenanthos,[2] and again in his 1995 treatment of the genus for the Flora of Australia series.