The UWI's Latin Motto, which appears on its armorial bearings, is "Oriens Ex Occidente Lux" which means "Light Rising From the West." The motto was first proposed by the Principal of Queen's Royal College, Trinidad, Mr. R.M. Homer, and almost identical wording was suggested by Mr. Maurice Platnaver of Brasenose College, Oxford.

A number of suggestions for the motto were advanced at the time. The Principal's own suggestion was "the first three words of the epitaph on the grave of Jeremiah Harrocks, who first observed the transit of Venus. The Honourable L.C. Hannay who represented Trinidad on the Provisional Council suggested fourteen possible mottos in Latin, including: "Mihi Dulcus Imago Posiluit" (She has grown up my own sweet image) and "Par Operi Sedes" (Well suited to the work are its surroundings).

The chosen motto was approved by Council at a meeting in January, 1949.

Records relating to the selection of the University's Motto are available for viewing at the University Archives, Mona under Archives Accession Nos. MA92.1 and MA98.34.