Lewis & Short

†† arinca, ae, f. [Gallic], a kind of grain, otherwise called olyra, Plin. 18, 8, 19, § 81; 18, 10, 20, § 92; 22, 25, 27, § 121.
Acc. to Harduin, rye (in Dauphiné, now riguet); acc. to others, the one-grained wheat: Triticum monococcum, Linn.