"Food" and "oat": a note on the etymology of Gk. ... and NE. oat

In other parts of Romania the meaning was "barley": Sp. cebada, Port, ceveda.1 The semantic difference reflects the nature of the food or fodder predominant in the respective area.2 A similar case is that of Rheto-Romance (Engadin) fiber "oat", (Grigioni, Puschlav) flodar "grain", (Grigioni, Misox) freda "fodder" from Frankish fodr "nourishment" = OIce. födr, OE. födor, OHG. fuotar "fodder"3. From many medieval sources we learn that for northern European peoples (Germans, Scandinavians, and Celts of Britain) oat played a crucial role in their nourishment.15 The old hypothesis of W.WSkeat16, followed by Buck17 and accepted with doubts by Walde/Pokorny18 and Pokorny19, connecting oat with Ice. eitill "nodule in stone", Norw. eitel "gland, knot, nodule in stone", Russ. jadro "kernel in fruit, bullet, ball", Gk. e?d?? "swelling", all from *oid- "to swell", is unlikely semantically, no words for "grain" being associated with this root20. [...]OE. cete "oats", recorded around 1000 A.D. (genim bean mela oþþe oetena "take bean or oat meal"25), is the regular development of IE. *ed- "food" and so is also OE. oet (gen. oetes) m., cet (gen. oete) f. "food, eating, meal", first attested around 1000 A.D.26 But the problem is why ate, not cète, is almost the only recorded form for "oats"? [...]Edition.