board

Concise Oxford English Dictionary © 2008 Oxford University Press:
board/bɔːd/

▶noun

• 1 a long, thin, flat piece of wood used for floors or other building purposes.

  ■ (the boards) informal the stage of a theatre.

• 2 a thin, flat rectangular piece of stiff material, e.g. a chopping board or noticeboard.

  ■ the piece of equipment on which one stands in surfing, skateboarding, etc.

• 3 [treated as sing. or pl.] the decision-making body of an organization.

• 4 the provision of regular meals in return for payment or services.

  ■ archaic a table set for a meal.

• 5 Sailing a distance covered by a vessel in a single tack.

▶verb

• 1 get on or into (a ship, aircraft, or other vehicle).

  ■ (be boarding) (of an aircraft) be ready for passengers to get on.

• 2 live in someone's house and receive meals in return for payment or services.

  ■ (of a pupil) live in school during term time in return for payment.

• 3 (board something up/over) cover or seal a window or building with pieces of wood.

• 4 (as adj. boarded) made of wooden boards.

• 5 ride on a snowboard.

– phrases
go by the board (of a plan or principle) be abandoned, rejected, or ignored. [from naut. use meaning ‘fall overboard’, board meaning the side of the ship.]
on board

• 1 on or in a ship, aircraft, or other vehicle.

• 2 informal on to a team as a member.

take something on board informal fully consider or assimilate a new idea or situation.
tread the boards informal appear on stage as an actor.

– derivatives
boarding noun.

– origin OE bord, of Gmc origin; reinforced in ME by OFr. bort ‘edge, ship's side’ and ON borth ‘board, table’.