Trend
Definition
The general direction of price movement - upward (bullish), downward (bearish), or sideways (ranging).
Detailed Explanation
A trend is the overall direction that an asset is moving. An uptrend consists of higher highs and higher lows. A downtrend consists of lower highs and lower lows. Sideways/ranging markets have neither. 'The trend is your friend' is a trading principle suggesting trades in the trend direction have higher success rates. Trends exist on multiple timeframes simultaneously - you might have an uptrend on weekly charts but a downtrend on daily charts.
Example
AAPL makes higher highs ($170, $180, $190) and higher lows ($165, $172, $182) = uptrend. Look for buying opportunities at higher lows.