What does the word nerve mean?

Usage examples for nerve

  1. I have a nerve to ask any girl to do it! – Saturday's Child by Kathleen Norris
  2. No good telling her it's nerve not body that he ain't got. – The Emigrant Trail by Geraldine Bonner
  3. Not unless my young friend here gets his nerve up. – The Enchanted Canyon by Honoré Willsie Morrow