Poliocephalus and its counterparts poliocephala and poliocephalum are Greek words meaning 'grey-headed'. Poliocephalus is the name for a genus of grebes, while Poliocephala is the name for a genus of flies. The two words are often used as the second word of a binomial name.
Species names poliocephalus or poliocephala could refer to any of the following:
Mammals
the grey-headed flying-fox, Pteropus poliocephalus a tayra subspecies, Eira barbara poliocephala the white-headed langur, Trachypithecus poliocephalus
Birds
the ashy-headed goose Chloephaga poliocephala the brown-chested alethe Pseudalethe poliocephala the gray-crowned palm-tanager Phaenicophilus poliocephalus the gray-crowned yellowthroat Geothlypis poliocephala the grey-crowned flatbill Tolmomyias poliocephalus the grey-headed babbler Stachyris poliocephala the grey-headed greenbul Phyllastrephus poliocephalus the grey-headed swamphen Porphyrio (porphyrio) poliocephalus the hoary-headed grebe Poliocephalus poliocephalus the island thrush Turdus poliocephalus the lesser cuckoo Cuculus poliocephalus a little tinamou subspecies Crypturellus soui poliocephalus the mountain nightjar, Caprimulgus poliocephalus the New Guinea goshawk Accipiter poliocephalus the pink-bellied imperial pigeon Ducula poliocephala the west Mexican chachalaca Ortalis poliocephala the yellow-lored tody-flycatcher Todirostrum poliocephalum
Insects
the moth Acrocercops poliocephala the fly Trentepohlia poliocephala