(τροχίλος; trochílos). Cavetto moulding, a concavely curved element in a Classical Attic/Ionic column base separating the upper and lower convex shaped tori (Torus); also current in Archaic/Ionic architecture as a formative element of representational column bases (Column II. B.3. with ill.). The contours of the trochiloi of the column bases in the archaic Temple of Hera on Samos , turned on a lathe and of remarkably varied shape, are famous.
Ebert, 26 (terminology and etymology)
Ch. Höcker, Sekos, Dipteros, Hyp…