σφενδόνη

1. Lat. funda (the ς being lost), a sling , (Iliad by Homer): metaphorically, σφενδόνας ἀπ᾽ εὐμέτρου with well-measured throw, as from a sling , (Aeschulus Tragicus)

2. the hoop of a ring in which the stone was set as in a sling, especially the broader part round the stone , as in Lat. funda for pala annuli , (Euripides)

3. the stone or bullet of the sling , (Xenophon Historicus); τοιαύταις σφ., of hailstones, (Aristophanes Comicus) (ML)