herculean

the word herculean derives from the name of the roman hero hercules, the latin adaptation of the greek herakles. in classical mythology, hercules was famed for completing twelve superhuman labors of immense strength and difficulty. the adjective-forming suffix -an was attached to his name in english to create a term meaning "pertaining to or characteristic of hercules." thus, herculean evolved from a literal reference to the hero's legendary feats to its modern abstract meaning, describing any task requiring extraordinary strength or effort.

Structure: hercule (hercules) + an (adjective suffix) hercule (from latin hercules, the roman hero, from greek herakles, meaning "glory of hera") + an (english adjective-forming suffix, from latin -anus, meaning "pertaining to")