What does the word maniac mean?

Usage examples for maniac

  1. Some members of the police entered, and took the maniac away. – Mabel's Mistake by Ann S. Stephens
  2. Why, by this time she's a raving maniac! – The Living Link by James De Mille
  3. I had seen her a raving maniac. – Isaac T. Hopper by L. Maria Child