1(Also Pallas' warbler, Pallas's leaf warbler, Pallas's willow warbler) a very small warbler, Phylloscopus proregulus (family Sylviidae), native to central Asia with predominantly olive-green plumage and a pale crown stripe.

2(More commonly Pallas's grasshopper warbler) a small warbler, Locustella certhiola (family Sylviidae), native to central and eastern Asia and resembling the grasshopper warbler L. naevia, with predominantly olive-brown plumage but white-tipped tail feathers and a brownish rump.