חָזַק

From LSJ

τὸ δ' ἡδέως ζῆν καὶ ἱλαρῶς οὐκ ἔξωθέν ἐστιν, ἀλλὰ τοὐναντίονἄνθρωπος τοῖς περὶ αὑτὸν πράγμασιν ἡδονὴν καὶ χάριν ὥσπερ ἐκ πηγῆς τοῦ ἤθους προστίθησιν → but a pleasant and happy life comes not from external things, but, on the contrary, man draws on his own character as a source from which to add the element of pleasure and joy to the things which surround him

Source

English (Strong)

a primitive root; to fasten upon; hence, to seize, be strong (figuratively, courageous, causatively strengthen, cure, help, repair, fortify), obstinate; to bind, restrain, conquer: aid, amend, X calker, catch, cleave, confirm, be constant, constrain, continue, be of good (take) courage(-ous, -ly), encourage (self), be established, fasten, force, fortify, make hard, harden, help, (lay) hold (fast), lean, maintain, play the man, mend, become (wax) mighty, prevail, be recovered, repair, retain, seize, be (wax) sore, strengthen (self), be stout, be (make, shew, wax) strong(-er), be sure, take (hold), be urgent, behave self valiantly, withstand.