Middle English retenprobably from Middle Dutch reeten
American Heritage Dictionary of the English Language, 5th Edition
Ret Sentence Examples
D, Transverse section of a retinula of the lateral eye of Limulus, showing ten retinula cells (ret), each bearing a rhabdomere (rhab).
A, Diagram of a retinula of the central eye of a scorpion consisting of five retina-cells (ret), with adherent branched pigment cells (pig).
Fresh translations of Aristotle and Averroes had already been made from the Arabic (IIepi ret ivropiat from the Hebrew) by Michael Scot, and Hermannus Alamannus, at the instance of the emperor Frederick II.; so that the whole body of Aristotle's works was at hand in Latin translations from about 1210 to 1225.
The reverse bears the motto Ret og Sandhed (Right and Truth).