requiring a great deal of effort or strength, physical and/or mental, very difficult, powerful, extensive, or intense (may be used as "herculean" or "Herculean");
e.g. It would take a Herculean effort to be able to fix the school in time.
(adjective)
physically strong and muscular in build (may be used as "herculean" or "Herculean");
e.g. The athlete was very tall and had a Herculean physique.