tētrăchordos, on, adj., = tetra/xordos, on,having four strings or notes.I.Adj.: machina,
a water-organ
, Vitr. 10, 13. —II.Subst. tētrăchordon (-dum), i, n., a chord of four notes, a tetrachord.A.Lit., Vitr. 5, 4; Mart. Cap. 9, 935 and 941; Macr. S. 1, 19 med.—B.Trop.: anni, i. e. the four seasons, Varr ap. Non. 71, 16.