Why it matters
Liquidity vacuums are where stops become market orders into emptiness. You get filled far from your level because there is no one to trade with.
Trading use: the point is not vocabulary. The point is prediction: what changes when this shows up?
Common trap
Believing ‘liquidity is always there’ in major pairs. In stress, everyone becomes a liquidity taker and the book thins aggressively.
Example
A surprise headline hits. Price jumps 15 pips with almost no prints in between. Stops trigger, but fills land near the end of the jump.
Operational cue: if you can’t point to it on the chart, in the DOM, or in your broker logs, treat it as a story and trade smaller.
Notes
Quick rule
- If you see this repeatedly, you are in a different regime than your model assumes.
- Regime change usually means position size change.
- When in doubt: trade smaller, or don’t trade.