What Is a Piker?
Piker is a broker or investor who makes small size trades. Piker is a pejorative slang term used to describe jejune individuals who are said to have limited impact on the operations of the market or a business.
An individual is most likely to be considered a piker if they makes small trades or do not prepare fully for the trading day. The word itself is thought to be more offensive than a term such as “amateur." An individual who believes them self to be very knowledgeable about investing, despite evidence indicating otherwise, would be considered a piker.
Professional brokers or investors may consider investors who don’t work in a formal setting as pikers. They would look down on this group as a bunch of amateurs; day traders are thrown into this pile of pikers in their minds. This may be fueled by the idea that day traders work from home in their pajamas, waking up right before the opening bell and trading without researching securities with the same attention to detail as professionals who study markets and securities for a living. Because of this scornful attitude on the part of professional brokers and investors, calling someone a piker face-to-face is generally something that's not done.
In another sense, the word piker is used to describe an investor who transacts in ways considered outside of the ordinary compared to normative practices by brokers. In addition to being compared to an amateur investor, piker may be used to describe a professional broker who submits an odd unit of trading in a deep market. For example, a broker may place an order for $5,000 worth of a security. Another broker may consider this so insignificant as to be laughable, and would not want to waste time handling the order. However, if they are bored at the moment and deigns to execute the order, if only for a small commission, they'll do it - and then share a joke with their buddy about the piker.