board [OE] It is more difficult to cheat at cards if your hands are clearly visible above the table. This is where the expression above board [L16th] comes from. Board is an old word for table, as well as the planks that make it, and if a card player was playing ‘above board’ they were showing that they were not trying to cheat. The members of the board that runs a company typically sit round a large table in the boardroom [[M19th], and it is again the meaning ‘table’ that gives them their name. See also cabinet.

The expression across the board [E20th] originally comes from horse racing. A bet made ‘across the board’ is one in which you stake equal amounts of money on the same horse to win a race, to come second, or to finish in the first three. The board [LME] here is one on which bookmakers write up the odds. Go by the board [M17th] was originally said at sea of masts and pieces of rigging that fell overboard. The board [OE] in this case was the side of the ship, and is used also in on board [LME], overboard [OE], and shipboard [ME].