What does "nog" mean?

Additional senses

1. 2.A wooden block, of the size of a brick, built into a wall, as a hold for the nails of woodwork.
2. 3.One of the square logs of wood used in a pile to support the roof of a mine.
3. 4.(Shipbuilding) A treenail to fasten the shores.
4. 5.To fill in, as between scantling, with brickwork.
5. 6.(Shipbuilding) To fasten, as shores, with treenails.