plain
...be as plain as a pikestaff / to be as

Plain Antvireo
Dysithamnus mentalis

Plain Chachalaca
Ortalis vetula

Plain Flowerpecker
Dicaeum minullum

Plain Gerygone
Gerygone inornata

Plain Greenbul
Eurillas curvirostris

Plain Honeyeater
Pycnopygius ixoides

Plain Inezia
Inezia inornata

Plain Laughingthrush
Pterorhinus davidi

Plain Leaf Warbler
Phylloscopus neglectus

Plain Mountain Finch
Leucosticte nemoricola

Plain Nightjar
Caprimulgus inornatus

Plain Parakeet
Brotogeris tirica

Plain Pigeon
Patagioenas inornata

Plain Prinia
Prinia inornata

Plain Softtail
Thripophaga fusciceps

Plain Sunbird
Anthreptes simplex

Plain Swift
Apus unicolor

Plain Thornbird
Phacellodomus inornatus

Plain Xenops
Xenops minutus

Plain-backed Sparrow
Passer flaveolus

Plain-breasted Hawk
Accipiter ventralis

Plain-breasted Piculet
Picumnus castelnau

Plain-brown Woodcreeper
Dendrocincla fuliginosa

plain-clothes
plain-clothes policeman

Plain-colored Seedeater
Catamenia inornata

Plain-colored Tanager
Tangara inornata

Plain-crowned Spinetail
Synallaxis gujanensis

Plain-winged Woodcreeper
Dendrocincla turdina

protractor
plain protractor