zori `Luck'. This word is unusually interesting. It is attested in early texts as meaning `omen', and the great Basque linguist Michelena reconstructs the original sense as simply `bird'. Centuries ago it was a common practice to try to foretell the future by studying the flight of birds, and the Basque word for `bird' came to have the sense of `omen'. It is the palatalized form of this word, (t)xori, which is today the universal Basque word for `bird'.

Source: Some Basque Words