ἰθύκυφος
From LSJ
Τὸ μανθάνειν δ' ἥδιστον εὖ λέγοντος, εἰ κέρδος λέγοι → It is the sweetest thing to learn from one speaking well, if they speak profitably
English (LSJ)
η, ον, of parts of the normal spine,
A frontally concave, Hp.Art.45 (ἰθυ-κῡφής, ές,Mochl.1); opp. ἰθύ-λορδος, η, ον (ος, ον Mochl.l.c.), frontally convex, ll. cc., cf. Gal.18(2).542.