σιδηροφυής
From LSJ
κάλλιστον ἐφόδιον τῷ γήρᾳ ἡ παιδεία (Aristotle, quoted by Diogenes Laertius 5.21) → the finest provision for old age is education
English (LSJ)
ές, (φύω)
A of iron nature, dub. l. in Poll.7.106, where Bekker (after cod. A, -φύσσα) reads σιδηρόφῡσα, forge-bellows.