Webster's Revised Unabridged Dictionary · 1913

Herculean

Herculean , adjective

[Latin herculeus, from Hercules: compare French herculéen. See Hercules.]

1.
Requiring the strength of Hercules; hence, very great, difficult, or dangerous; as, an Herculean task.
2.
Having extraordinary strength or size; as, Herculean limbs.
Herculean Samson. — Milton