στερρότης
From LSJ
ἀσκέειν, περὶ τὰ νουσήματα, δύο, ὠφελέειν, ἢ μὴ βλάπτειν → strive, with regard to diseases, for two things — to do good, or to do no harm | as to diseases, make a habit of two things — to help, or at least, to do no harm
English (LSJ)
ητος, ἡ, (στερρός (A))
A hardness, firmness, τοῦ πάγου, of ice that will bear, Plu.2.969a; [τῶν ἀτόμων] Epicur.Fr.282: metaph., firmness, Ph.1.276. II (στερρός (B)) barrenness, Arist.GA773b27.