κρίσιμος
From LSJ
Μέλλοντα ταῦτα. Τῶν προκειμένων τι χρὴ πράσσειν· μέλει γὰρ τῶνδ' ὅτοισι χρὴ μέλειν → Tomorrow is tomorrow. Future cares have future cures, and we must mind today.
English (LSJ)
[ῐς], ον, (κρίσις)
A decisive, critical, κ. ἡμέρα the crisis of a disease, Hp.Aph.7.85, al., Arist.Ph.230b5; κ. γὰρ αὕτη γίγνεται (sc. the seventh day) Men.890; also κ. φάεα AP11.382.11 (Agath.); ἐν κρισίμοις Hp.Epid.1.7: Comp. -ώτερος Id.Acut.23. Adv. -μως Id. Epid.l.c.