1. boldness or daring; courage. 

2. audacity or impudence; insolence. 

3. strength; power; vigor: the hardihood of youth. 

4. hardy spirit or character; determination to survive; fortitude.

Etymology: from English hardy, from Middle English hardi < Old French, past participle of *hardir, “to harden, make brave” < Germanic; compare Gothic -hardjan, Old High German hartjan, “to harden” + -hood, suffix for indication of state or condition of being, from Old English -hād.

[Aldo Katayanagi - Hellboy]