Noun

1. A stock broking firm which takes small orders from clients and takes them on its own account rather than actually transmitting them to the market. Often setup as shop-fronts in the 1920s.
2. A stock broking firm which sells stock to clients when it has an undisclosed relationship with that company or its owners.
3. (travel industry) (dated) a travel agency selling discounted airfares, usually in defiance of existing minimum fare arrangements. Now usually refers to any small cheap agency.
4. a legal services firm selling heavily discounted legal services in large volume, sometimes as a white labelled loss leader product.