An odd lot is a securities trade made for less than the normal trading unit. If you are talking about stocks, an odd lot would generally be a trade of less than 100 shares. The number differs for other types of securities, though. In some cases, because of the size of the order, odd lot orders can have a higher commission. These are also occasionally called a broken lot or an uneven lot. If a trader is buying or selling an odd lot, it probably means that they have limited funds to invest.