What does the word fathom mean?

Usage examples for fathom

  1. I felt there was some strange mystery which I could not fathom, but what was my surprise, when, as I went into the sitting- room, I heard the blind girl say in a melancholy tone of voice- " 'No, father, I would rather not see at all to- day than lose my eyes. – The Man-Wolf and Other Tales by Emile Erckmann and Alexandre Chatrian
  2. I've tried to fathom it in the last hour, but it's too deep for me; I give it up. – Her Infinite Variety by Brand Whitlock