Definitions of heroic:

• noun:   a verse form suited to the treatment of heroic or elevated themes; dactylic hexameter or iambic pentameter
• adjective:   impressive in size or scope

  Example: "Heroic undertakings"

• adjective:   relating to or characteristic of heroes of antiquity

  Example: "Heroic legends"

• adjective:   having or displaying qualities appropriate for heroes

  Example: "The heroic attack on the beaches of Normandy"

• adjective:   very imposing or impressive; surpassing the ordinary (especially in size or scale)

  Example: "Of heroic proportions"

• adjective:   showing extreme courage; especially of actions courageously undertaken in desperation as a last resort

  Example: "They took heroic measures to save his life"