retral
/ˈrɛtr(ə)l/adjective
1Chiefly Zoology and Palaeontology. Posterior; situated at or towards the back; facing backwards.
2Of a movement or direction: backwards. rare.
Origin
Early 19th century; earliest use found in John Fleming (1785–1857), naturalist and Free Church of Scotland minister. From classical Latin retrō retro + -al.