A marketable bond means there is a market willing to purchase the securities. Aliquid market means one can make purchases and sales of the security easily without much of a sacrifice in price, since the securities trade abundantly. For example: An issuer has securities to sell and there are only a few willing buyers but they will snap up the entire issue. In this case the securities are marketable (since there is a ready market to buy the shares) but the issue probably won't be very liquid (since only a few people are interested, it isn't likely that there will be a lot of trading. That means when someone goes to sell his or her shares, they may not get a great price for the sale since so few people are trading in the issue). For example: an issuer has securities to sell and thousands of investors are interested in the issue and there will be much competition to own the shares. This issue would be marketable (since there is a ready and willing market to buy the shares) and will likely be very liquid (since so many people will likely be trading the shares back and forth each day, it will be easy for a buyer or seller to place his or her order and get something close to the desired price).