HERCU'LEAN, adjective [from Hercules.] Very great, difficult or dangerous; such as it would require the strength or courage of Hercules to encounter or accomplish; as herculean labor or task. 1. Having extraordinary strength and size; as herculean limbs. 2. Of extraordinary strength, force or power.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI