λεπτότης · leptotēs — LSJ
thinness, opp. παχύτης, Hp. VC 2.
fineness, delicacy, opp. πάχος, Pl. R. 523e, al.; of soil, Arr. Tact. 34.1; of the air, tenuity, Pl. Ti. 58b, Arist. Cael. 303b24, cf. Ph. 215b28: in pl., opp. πάχη, Id. HA 507b26; of the εἴδωλα, Epicur. Ep. 1p.10U.
thinness, meagreness, of body, Pl. Lg. 646b.
metaph., subtlety, τῶν φρενῶν Ar. Nu. 153, cf. Luc. Bis Acc. 2.