Room and Board 里的 board 就是提供膳食的意思。 http://en.wikipedia.org/wiki/

"Board" refers to the table on which food is served. Historically, "in a modest house, the table, or 'board', might have been provided with stools for guests but just the one chair with arms, which was reserved for the household's head. The original 'chairman of the board' was literally so seated on a chair while everyone else was on a stool..."