σκληρόω
From LSJ
νὺξ μὲν ἐμὸν κατέχει ζωῆς φάος ὑπνοδοτείρη → sleep-giving night hath quenched my light of life | sleep-giving night covers my light of life | night, the giver of sleep, holds the light of my life
English (LSJ)
A harden, in Pass., Xenocr. ap. Orib.2.58.28.
German (Pape)
[Seite 901] hart machen, härten, abhärten, Sp.