A grand division of birds, including all existing flying birds; -- So called from the carina or keel on the breastbone.
Source: Webster's dictionaryBeginning in the 1980s, Carinatae was given several phylogenetic definitions. Source: Internet
Carinatae is the group of all birds and their extinct relatives to possess a keel, or "carina", on the underside of the breastbone used to anchor large flight muscles. Source: Internet
Classification Definition Traditionally, Carinatae were defined as all birds whose sternum (breast bone) has a keel (carina). Source: Internet
An alternate definition was provided in 2001, naming Carinatae an apomorphy -based clade defined by the presence of a keeled sternum. Source: Internet