'anguine' originates from Latin, specifically the word 'anguineus,' where 'anguis' meant 'snake'.

'anguineus' in Classical/Medieval Latin was retained in New Latin scientific usage and eventually became the modern English adjective 'anguine'.

Initially, it meant 'of a snake' or 'snakelike,' and this sense has largely remained the same, with an added technical use in zoological classification (Anguidae).