καπνιστέον
From LSJ
Πυλάδη, σε γὰρ δὴ πρῶτον ἀνθρώπων ἐγὼ πιστὸν νομίζω καὶ φίλον ξένον τ' ἐμοί → Pylades for indeed I consider you, foremost among men, loyal and kind and a host to me (Euripides' Electra 82-83)
English (LSJ)
one must smoke, 'gas', τοὺς ἐν τοῖς μετάλλοις ὄντας Ph.Bel.99.18.
Greek (Liddell-Scott)
καπνιστέον: ῥημ. ἐπίθ. τοῦ καπνίζω, δεῖ καπνίζειν, Φίλων Μαθ. σ. 99.