[1] The hairy-backed bulbul was originally described in the genus Brachypodius (a synonym for Pycnonotus).
Alternatively, some authorities have classified the hairy-backed bulbul in the genera Trichophorus (a synonym for Criniger) and Hypsipetes.
It is olive above and yellowish below, with key features including pale yellowish lores and a broad eye ring, a dark rufescent olive-brown cap and neck, olive-rufous uppertail-coverts and upperwings, a bright rufous-brown tail with creamy white tips, a creamy white chin and throat merging into a yellow breast, and hair-like filoplumes on the back (often concealed).
Juveniles have a grey-brown iris and pale fleshy pink legs.
The subspecies sericeus is larger than the nominate form, with duller yellow undertail-coverts; and viridis is similar, but brighter on the upperparts.