A multiple resistance breakout through trendline occurs when the price of a stock consistently faces rejection from a downward or horizontal resistance trendline (formed by connecting multiple swing highs), but eventually manages to break above it with strong momentum. Each touch of the trendline represents resistance where sellers are active, and the more times price gets rejected, the stronger that resistance zone becomes. When the breakout finally happens—often accompanied by higher volumes—it signals that buyers have overpowered sellers, shifting the market sentiment from bearish or sideways to bullish. This type of breakout is considered more reliable since it clears multiple resistance levels at once, increasing the probability of a sustained upward move.