THRESHHOLD

The slate or wooden floors in wealthy homes would get slippery in the winter when wet. In order to prevent accidents, thresh (straw) was thrown on the floor. As the winter wore on, they kept adding more thresh until it would overflow through the door. A piece of wood was placed in the entrance-way to keep the thresh in the room. This wood in the doorway came to be known as

THRESHHOLD -- to hold the thresh