Zomma measures how an option’s gamma changes as implied volatility changes — a third-order Greek linking gamma and vol. It’s mostly a quant/dealer concern, but it completes the higher-order Greek picture.

What zomma captures

Gamma isn’t independent of volatility — a change in IV reshapes an option’s gamma profile. Zomma quantifies that: how much gamma shifts per point of IV change. It matters for traders and dealers running large, gamma-sensitive books who need to hedge as volatility moves, because their gamma exposure itself is moving underneath them.

Why it exists

For precise hedging, dealers can’t treat gamma as fixed when vol is changing — zomma tells them how their gamma (and thus their delta-hedging needs) will shift as IV moves. It interacts with vanna and vomma in the full second- and third-order hedging math that drives some market flows.

Zomma answers “how does my gamma change if volatility moves?” — a question only a large, precisely-hedged options book really needs to ask.

What it means for a scalper

Practically nothing directly — zomma is dealer/quant territory. Its value to you is conceptual: it shows how deep the hedging math goes, and why big options books generate flows that move the tape in ways no single first-order Greek explains. You trade the result (the dealer levels), not the zomma.