Option Flow Glossary: Call Wall, GEX, Put Wall, DEX & OI
Option flow glossary: short definitions of call wall, put wall, gamma exposure (GEX), DEX, DEI, Vol/OI, max pain, and related terms used in TradingFlow.
This option flow glossary (options flow terms included) is the quick map of words you will see across TradingFlow. Each entry has a one-line definition and a link to the full chapter.
For search-optimized single-term landers (what is a call wall, what is GEX, what is option flow, and more—with product surface mapping and FAQs), see the standalone Options glossary. Persona and comparison guides live under SEO guides.
Use this page when a table column, drawer tab, or SERP snippet mentions a word you want decoded fast. For the full learning path, start at Getting Started or the tutorial series hub.
Core flow terms
Option flow
Option flow is the live (or historical) stream of individual options trades—contract, size, premium, side, and timing—so you can see where money is printing, not only where price closed.
→ Full guide: Option Flow Concepts · Deep dive: What is option flow?
Unusual options activity (UOA)
Unusual options activity means a contract or symbol is trading far above its typical volume or size. It is a screen for attention, not a guaranteed signal.
→ Full guide: Option Flow Concepts · Deep dive: What is UOA?
Side (aggressive buyer / seller)
Side is inferred from where the trade printed relative to the bid/ask: at or above the ask usually means an aggressive buyer; at or below the bid usually means an aggressive seller.
→ Deep dive: Aggressor side
→ Full guide: Option Flow Concepts
Sentiment
Sentiment combines call vs put with aggressor side into a bullish, bearish, or neutral lean. Treat it as a shorthand, not proof of portfolio intent.
→ Full guide: Option Flow Concepts
Greeks and exposure
Delta
Delta estimates how much an option’s price moves when the underlying moves $1. Calls usually have positive delta; puts usually have negative delta.
→ Full guide: Greeks & GEX
Gamma
Gamma measures how fast delta changes as the underlying moves. High gamma means hedging pressure can shift quickly—especially near the money and near expiration.
→ Full guide: Greeks & GEX
Gamma exposure (GEX)
Gamma exposure (GEX) aggregates gamma from outstanding options from the dealers’ perspective. It frames whether dealer hedging is more likely to dampen or amplify price moves.
→ Full guide: Greeks & GEX · Deep dive: What is GEX? · Layered: GEX for day traders
Positive gamma / negative gamma
In a positive gamma regime, dealer hedging often works against the move (more range-bound). In a negative gamma regime, hedging often works with the move (more trend and volatility).
→ Full guide: Greeks & GEX
Delta exposure (DEX)
DEX converts an options trade into directional stock-like exposure (in TradingFlow: roughly delta × size). Larger absolute DEX means more directional weight behind the print.
→ Full guide: Delta Exposure (DEX)
Delta impact (DEI)
DEI scales DEX by the underlying’s typical stock volume so you can compare impact across cheap and expensive names more fairly.
→ Full guide: Delta Exposure (DEX) · Option Flow Concepts
Implied volatility (IV), IV Rank, IV Percentile
IV is the market’s priced-in expected move. IV Rank and IV Percentile place today’s IV in the stock’s recent history so “high” or “low” is contextual.
→ Full guide: Greeks & GEX
Chain structure and walls
Open interest (OI)
Open interest is how many contracts remain open (not closed or expired). Unlike volume, OI does not reset every morning and typically updates overnight.
→ Full guide: Option Chain & OI
Volume / open interest (Vol/OI)
Vol/OI is today’s volume divided by standing open interest—a fast freshness ratio. High Vol/OI means today’s activity is large versus what was already open.
→ Full guide: Option Chain & OI · Option Flow Concepts
ΔOI (change in open interest)
ΔOI is the day-over-day change in OI. After a big print, next-day ΔOI helps confirm whether positions likely opened, closed, or churned.
→ Full guide: Option Chain & OI
Call wall
A call wall is the strike with the largest call-side open interest (or call-side gamma concentration) above spot. It often acts as resistance when dealers hedge.
→ Full guide: Option Chain & OI · Deep dive: What is a call wall? · Layered: Call walls for index traders
Put wall
A put wall is the strike with the largest put-side open interest below spot. It often acts as support when dealers hedge.
→ Full guide: Option Chain & OI · Deep dive: What is a put wall?
Max pain
Max pain is the strike where the most options (calls and puts combined) would expire worthless. Near expiration, price sometimes gravitates toward it—treat it as a magnet, not a rule.
→ Full guide: Option Chain & OI
Zero-gamma / gamma flip
The zero-gamma (or gamma flip) level is where net GEX changes sign—a rough pivot between stabilizing and amplifying dealer-hedging regimes.
→ Full guide: Greeks & GEX
Product surfaces (where to look)
| You want… | Open this guide | Live app |
|---|---|---|
| Live prints, side, sentiment | Option Trades | Option Trades live |
| Loudest contracts | Rank Contracts | Rank Contracts |
| Ranked names + GEX/Chain drawer | Rank Symbols | Rank Symbols |
| Full concept path | Learn hub | — |
FAQ
Is this glossary a trading system?
No. Definitions help you read the product and market structure. They are not entry or exit rules.
Where should I start if I am new?
Getting Started → Option Flow Concepts → Greeks & GEX → Call wall / put wall.
How do I see these levels live?
Open Rank Symbols, pick a ticker, and use the GEX and Chain tabs in the symbol drawer.
See option flow, GEX, and walls in TradingFlow