Assurance

Noun

1. The act of assuring; a declaration intended to inspire full confidence; something designed to give confidence to someone.
2. The state of being assured; total confidence or trust; a lack of doubt; certainty; guarantee.
3. Firmness of mind; undoubting steadiness; intrepidity, courage, or self-confidence.
4. Excessive boldness; impudence; audacity

   "His assurance is intolerable."

5. Betrothal; affiance.