any of several species of tiny barbets, which, at 9 cm (3.5 inches), are the smallest of the family Capitonidae (order Piciformes). Tinkerbirds constitute the genus Pogoniulus. They are named for their metallic call—like a tinker mending pots—repeated unendingly in African forest and bush. Among the best known is the yellow-fronted tinkerbird (P. chrysoconus) of east-central Africa. It is glossy black above, with yellow rump and forehead, white eye stripes, and black moustache mark; the breast is pale gray, the belly greenish yellow.