ἀραίωσις
From LSJ
οὐ μακαριεῖς τὸν γέροντα, καθ' ὅσον γηράσκων τελευτᾷ, ἀλλ' εἰ τοῖς ἀγαθοῖς συμπεπλήρωται· ἕνεκα γὰρ χρόνου πάντες ἐσμὲν ἄωροι → do not count happy the old man who dies in old age, unless he is full of goods; in fact we are all unripe in regards to time
English (LSJ)
εως, ἡ,
A becoming or making porous, rarefaction, opp. πύκνωσις, dub. in Epicur.Nat.14Fr.11 (cf. Fr.6), cf. Plu.Strom.3, D.L.9.8 (Heraclit.), Corn.ND17, etc. 2 Medic., porosity, of the lungs, Hp. Oss.13, etc. 3 mordanting, PHolm. 8.3.
German (Pape)
[Seite 343] ἡ, das Dünnmachen, Auflockern, Arist. mund. 4 ὀμίχλη γίνεται ἐξ ἀραιώσεως νέφους; oft bei Hippocr. u. Sp., Ggstz πύκνωσις.