What does the word transom mean?

Usage examples for transom

  1. It was closed, but the transom above it was open, and all was darkness within. – Kitty's Conquest by Charles King
  2. West Fifty- Seventh Street was where I was established, in a hall bedroom on the top floor- a hall bedroom so form- fitting and cozy that when I went to bed I always opened the transom to prevent a feeling of closeness across the chest. – Cobb's Bill-of-Fare by Irvin Shrewsbury Cobb
  3. He ascended hastily two steps, which brought him to the level of the half- opened transom of the kitchen. – The Argonauts of North Liberty by Bret Harte