Welcome to the RJO Futures trading terms glossary. Within this glossary, you will find an expansive list of trading terms covering commodity, option, and futures trading terminology. Bookmark this section as a quick reference for definitions of trading terms as you browse the Internet and our site for more information on futures and options trading within the financial and commodities markets.
A person who sells an option and assumes the obligation to sell (in the case of a call) or buy (in the case of a put) the underlying futures contract at the exercise price. Also referred to as an Option Seller or Writer.