Options Trading Glossary

Delta measures the rate of change of an option's price relative to a $1 change in the underlying asset price. A Delta of 0.50 means the option price moves $0.50 for every $1 move in the underlying. For calls, Delta ranges from 0 to 1; for puts, from -1 to 0. Delta also approximates the probability of an option expiring in-the-money.

Gamma measures the rate of change of Delta relative to the underlying asset price. High Gamma indicates Delta will change rapidly with price movement. Options at-the-money (ATM) have the highest Gamma, which decreases as options move in-the-money or out-of-the-money. Critical for managing non-linear risk in options portfolios.

Theta measures the rate of time decay in an option's value, expressed as the daily dollar loss from the passage of time. For option sellers (short positions), Theta represents income as the option loses extrinsic value. Theta accelerates as expiration approaches, particularly for at-the-money options. The primary source of income in theta-harvesting strategies.

Vega measures an option's sensitivity to changes in implied volatility. A Vega of 0.10 means the option price changes $0.10 for every 1% change in implied volatility. Long options have positive Vega (benefit from rising IV), while short options have negative Vega. Essential for volatility trading strategies and understanding how market fear affects positions.

An Iron Condor combines a bull put spread (selling a put, buying a lower-strike put) with a bear call spread (selling a call, buying a higher-strike call). This creates a profit zone between the short strikes. Maximum profit equals the net premium received. Maximum loss is limited to the spread width minus premium. Ideal for range-bound, low-volatility environments.

A Credit Spread involves selling a higher-premium option and simultaneously buying a lower-premium option of the same type (both calls or both puts) with the same expiration. The net credit received is the maximum profit. A bull put spread profits when price stays above the short strike; a bear call spread profits when price stays below. Defined risk, defined reward.

A Calendar Spread (horizontal spread) involves selling a near-term option and buying a longer-term option at the same strike price. Profits from the faster time decay of the short-dated option relative to the long-dated option. Works best when the underlying stays near the strike price. Can be constructed with calls or puts for a similar risk profile.

A Long Straddle involves buying both a call and a put at the same strike price and expiration. Profits from large price moves in either direction. The breakeven points are strike ± total premium paid. A Short Straddle (selling both) profits from price staying near the strike but carries unlimited risk. Used when expecting a significant move but uncertain of direction.

A Long Strangle involves buying an out-of-the-money call and an out-of-the-money put with the same expiration. Lower cost than a straddle but requires a larger move to profit. A Short Strangle (selling both) collects premium and profits if price stays between the strikes. Wider profit range than a straddle but still carries significant risk on large moves.

A Butterfly Spread uses three strike prices: buy one option at a lower strike, sell two at a middle strike and buy one at a higher strike (all same type and expiration). Maximum profit occurs if the underlying closes exactly at the middle strike. Low cost and defined risk. Ideal when expecting minimal price movement and trading near a specific price target.

A Diagonal Spread combines elements of vertical and calendar spreads by using options with different strikes AND different expirations. Typically involves selling a near-term option and buying a longer-term option at a different strike. Offers more flexibility than pure calendars or verticals. Used to express views on both direction and volatility term structure.

Implied volatility is the market's forecast of likely movement in an asset's price, derived from option prices using models like Black-Scholes. Higher IV means options are more expensive. IV typically rises during market uncertainty (fear) and falls during calm periods. Unlike historical volatility, IV is forward-looking and reflects supply/demand for options.

IV Rank measures current implied volatility relative to its historical range over the past 52 weeks. An IVR of 80% means current IV is higher than 80% of readings in the past year. High IVR (>50%) suggests elevated premiums, favoring selling strategies. Low IVR (<30%) suggests cheap options, favoring buying strategies. Essential for timing options trades.

Max Pain is the strike price where the largest number of open option contracts (puts and calls) would expire worthless, causing maximum financial loss to option buyers. The theory suggests that market makers and large institutions may push the underlying price toward this level near expiration to minimize their payouts.