[In sense 1, ad. Gr. τὸ τετράγραμμον (Clem. Alex., 666), ‘the (word) of four letters,’ f. τετρα- four- + γράμμα letter; in sense 2 from γραμμή stroke, line.]
1. A word of four letters; = next.
1870. Brewer, Dict. Phrase & Fable, s.v. Tetragrammaton, The Greek Zeus, Latin Jove and Deus, Persian Soru, Assyrian Adad, Arabian Alla, Egyptian Amon, German Gott, and a host of other words significant of Deity, are tetragrams.
1882–3. Schaff’s Encycl. Relig. Knowl., I. 27. The Jews pronounced the tetragram YHWH by giving to it the vowels of Adonai.
2. Geom. The figure composed of four straight lines in a plane and their six points of intersection: commonly called complete quadrilateral.
1863. R. Townsend, Mod. Geom., I. vii. 145. Thus, for instance, in a tetrastigm or tetragram every line of connection of two points or point of intersection of two lines is said to be the opposite of that of the remaining two.
