What's a bourse? I read it in my finance class.

A bourse is an organized market or center where securities or commodities are bought and sold. These days, you might know it as a stock exchange. In Uncle Tom's Cabin, however, the word had a heinous attribute: It was the place where men, women, and children were to be sold as slaves:

There is a brisk lookout on [grooming and dressing]; injunctions passed around to everyone to put on their best face and be spry; and now all are arranged in a circle for a last review, before they are marched up to the Bourse.