See, more fully, Hesychius omicron1350 s.v o)/ruc.
The best known animal, the desert antelope Oryx leukoryx, was once widespread in Egypt, Arabia and Palestine (cf. Deuteronomy 14:5 LXX) but was hunted to extinction there. (There are recent attempts to reestablish it.) It is an aggressive animal, using its horns in battles for dominance or to rip open an enemy’s stomach. Its distinctive shape (web address 1) makes it easily recognizable in art ever since the earliest prehistoric designs, and it was hunted for its meat, prized as a delicacy in ancient Egypt and throughout Arab history, and for its tough skin, used in shields and leather. Damascius (Life of Isidore fr.102 Zintzen; cf. Photius, Bibliotheca 242.343a12) reports that the Egyptians believed it sneezed at the appearance of the star of the goddess Sothis (Sirius, whose appearance in the morning sky in June marked the new year and the season of the Nile floods). See the sympathetic account by Bonnet in 1908, who knew it when it was still hunted, and a video put out by Time-Life, available in the French periodical Sauvages as vol. 18. Other species remain vigorous in the African deserts, to which they have adapted themselves. See web address 2.
It apparently owes its Greek name to the shape of its horns, reminiscent of a 'stone-cutting tool', the proper meaning of the word (e.g. the first and primary gloss in Hesychius: see above ). At Greek Anthology 6.297 the oryx is described as mono/ruga ('having one pickaxe for a horn', see below); cf. tau 1148 and the series of notes on the reading at Pollux 10.147 cited there. A bent pick of this sort would be used for hewing stone by gouging out flakes of stone in a row to create a fault-line in the rock, and suggests the ancient technique of incising and raising heated metal; the related verb o)ru/ssw (omicron 650) refers to trenching, gouging or any fashion of making a channel.
The animal uses his horns to rip open an enemy's stomach, in a gesture reminiscent of the root from which Hephaestus' chasing tool in Homer, r(ai/sthr, is derived; see tau 375. Oddly, Aristotle believed that the antelope had only one horn, like the unicorn, probably confusing the animal (HA 499b19, PA 663a22-3a25) with the tool and the narwhal (see below).
The name oryx was also used for an Indian four-horned antelope (Tetraceros quadricornis: Aelian, NH 15.14; cf. a gazelle, 13.25 ), the narwhal or some other large horned fish (Strabo 3.2.7), a boat with a bowsprit, and a bird reported in Eusebius, Comm. Is. 2.40, 46,48ff., citing the proverb '[crazy as] an oryx in a net' (but a proverb most likely referring to the aggressive desert antelope).