BTC- Buy to Close
BTO - Buy to Open
OI - Open Interest
OI/Max Pain - My altered take on the original dollar value Max Pain theory. I use OI and a range. My studies have led me to use different data points. I call it OI/Max Pain.
Pinning - When a stock volleys back and forth on a strike closing at or near it. It must be noted: this is not manipulation. This is caused by a high volume of put and call buyers closing out their positions near the close of trading.
Risk Trade - Any type of trade that causes 100% loss or is binary in its outcome. An example would be selling a credit spread on the highest OI put/call strike. This money goes away forever if wrong. I really only consider credit spreads as risk trades.
STC - Sell to Close
STO - Sell to Open