(Part of the) common name of many of the larger species of the family Anatidae especially in the tribe Anserini or 'swans and true geese' of the subfamily Anserinae. But the name is also used in other tribes and subfamilies in such a way that 'ducks' and 'geese' cannot be taxonomically separated. The name is sometimes misused for Morus bassanus as 'Solan Goose' (a gannet), and Gavia immer as Ember Goose (a diver). Goose is sometimes used to indicate the female only, in contradistinction to 'gander' for the male; 'gosling' is used for the young. See also: 'duck(s)'. The members of the family are essentially aquatic, but true geese are for the most part much less aquatic in habit. All Anatidae have relatively long necks, blunt, rather spatulate bills and three of the toes are linked by webs. Usually the females line their nests with down plucked from the breast and the young of all species leave the nest soon after hatching (nidifugous). Most geese moult the flight feathers simultaneously and have a flightless period of three to four weeks after the breeding season. True geese (14 species, subfamily Anserinae) can be divided into 'grey geese' (Anser spp.) and 'black geese' (Branta spp.). They are wary birds which graze in flocks ('gaggles') and fly in 'skeins' (V-shaped group pattern). They are confined to the Northern Hemisphere and most breed in arctic or subarctic latitudes and have strong migratory habits. In spite of these migrations many species can be divided into well marked geographical races which preserve their reproductive isolation because of strong family and group bondings. Unlike most ducks they don't show sexual dimorphism in plumage. The typical grey goose Anser anser or Grey Lag Goose (widespread Palaearctic species) gave rise to various domestic forms of farmyard geese. In the subfamily Anatinae, the tribe Tadornini contains the sheld geese (and -ducks) and the tribe Cairinini the perching geese (and -ducks) among which are the remarkable Pygmy Geese, the smallest Anatidae (in fact tiny perching ducks). The Magpie Goose forms the sole member of the subfamily Anseranatinae, which is rather aberrant and apparently primitive (e.g., only slightly webbed toes and no special flightless period).

Alternative forms for geese : Anser, Branta, gander, goose, gosling.