What is a liquidity sweep in trading?
Above swing highs sit buy stops: the stop losses of short sellers and the orders of breakout buyers. Below swing lows sit sell stops. ICT calls them buy-side and sell-side liquidity. Equal highs or equal lows are the most obvious pools, because so many traders place stops just beyond them.
A sweep happens when price trades through that level, fills those orders, and then closes back on the original side. The wick beyond the level is the sweep. A breakout is different: price closes beyond the level and keeps going.