OCO
One Cancels the Other is a contingent order where the execution of one part of the order automatically cancels the other part.
Open Order
An order that will be executed when a market moves to its designated price; normally associated with Good-Till-Cancelled Orders.
Open Position
An active trade with corresponding unrealized P&L, which has not been offset by an equal and opposite deal.
Option
An agreement that allows the holder to have the option to buy/sell a specific security at a certain price within a certain time. (Two types of options – call and put; a call is the right to buy while a put is the right to sell. One can write or buy call and put options.)
Order
An order is an instruction, from a client to a broker to trade. An order can be placed at a specific price or at the market price. Also, it can be good until filled or until close of business.
Overnight Position
A trade that remains open until the next business day.