Erbum latini quod greci orbum dicunt.
greci orbum ACD | orbum (orobum f) greci B ef
Erbum is what Latin speakers say and Greeks say orbus.
Latin ervum, also herbum, is glossed by Lewis & Short: "a kind of pulse, the bitter vetch, ervum ervilia, Linn".
Greek ὄροβος /órobos/ id., was loaned into Latin as orobus; Simon's form in most witnesses is orbus.
Ervum ervilia L., syn. Vicia ervilia (L.) Willd. "bitter vetch" [], []. The wild strains of bitter vetch are found in Anatolia and parts of the Middle East. The pulse belongs to the eight Neolithic founder crops and has been cultivated ever since, today mainly restricted to Morocco, Spain and Turkey.
Bitter vetch grain is used as fodder, and Dioscorides Longobardus, 2, 91, ed. Stadler (1899: 215), De herbo, states explicitly: Elixus et datus vobes pinguescere facit - "Boiled and administered it makes oxen fat". He also mentions some use of it in medicine. As for human consumption, due to its extreme bitterness it must first be processed. Split, when it resembles red lentils, and leached by several changes of boiling water, it was mainly eaten during famine years.
Ervum, ὄροβος /órobos/ - although known to the botanical and medical authors of antiquity - was subject in their descriptions to occasional confusion with lentil, other vetches and chickpea.