Trendline
Technical Analysis
What it means
A straight line drawn across a series of higher lows (up trend) or lower highs (down trend) to make the trend visible. Price tends to respect it.
Example
In an up trend, you draw a line connecting the lows at $45, $50, $55. Price bounces off that line three times, confirming it as a valid up-trendline.
Mistake beginners make
Beginners redraw trendlines every time price pokes through, until the line fits their bias. A trendline that needs constant redrawing is not a trendline.