Insolent boldness, especially when imprudent or unconventional.
Fearlessness, intrepidity or daring, especially with confident disregard for personal safety, conventional thought, or other restrictions.
Excessive boldness; foolish daring; offensive assurance.
Unyielding boldness and daring; firmness in doing something that exposes one to difficulty, danger, or calamity; intrepidness.
Ability to withstand extreme conditions, hardiness.