At Home: A Short History of Private Life

by Bill Bryson

The dining table was a plain board called by that name. It was hung on the wall when not in use, and was perched on the diners’ knees when food was served. Over time, the word board came to signify not just the dining surface but the meal itself, which is where the board comes from in room and board. It also explains why lodgers are called boarders and why an honest person—someone who keeps his hands visible at all times—is said to be aboveboard.

In England the cabinet became the most exclusive and private of all chambers—the innermost sanctum where the most private meetings could take place. Then it made one of those bizarre leaps that words sometimes make and came to describe (by 1605) not just where the king met with his ministers, but the collective term for the ministers themselves. This explains why this one word now describes both the most intimate and exalted group of advisers in government and the shelved recess in the bathroom where we keep Ex-Lax and the like.