ἰσχύειν
From LSJ
Sunt verba voces quibus hunc lenire dolorem possis, magnam morbi deponere partem → Words will avail the wretched mind to ease and much abate the dismal black disease.
Greek > English (Woodhouse Verbs Reversed)
(see also ἰσχύω): powerful, be binding, be in force, be in vogue, be powerful, be rife, be strong, be valid, be vigorous, have power, have strength, possess vitality