See text Halcyon (/ˈhælsiən/) is a genus of the tree kingfishers, near passerine birds in the subfamily Halcyoninae.

The genus Halcyon was introduced by the English naturalist and artist William Swainson in 1821.

He named the type species as the woodland kingfisher (Halcyon senegalensis).

The genus Halcyon in the current sense consists mainly of species resident in sub-Saharan Africa, with a couple of representatives in southern Asia, one of which, the white-throated kingfisher, occasionally reaches Europe.

They are “sit and wait” predators of small ground animals including large insects, rodents, snakes, and frogs, but some will also take fish.