Related Clues:
- Advisory group
- Meals for money
- 'Hop aboard'
- Room partner
- Table game item
- Surfer's ride
- Part of a chess set
- Word that can follow the first words of 20-, 29-, 43- and 51-Across and 4-, 9-, 37- and 39-Down
- Chess need
- Piece of lumber
- Board, as a train
- Company leaders
- Climb aboard
- Make progress
- Get on the plane