1. streams or rivers that flow into a larger river or lake
Usage: geography
2. people, states, or nations that pay tribute to a more powerful ruler or country
Usage: historical

Examples

• The Mississippi River has many tributaries flowing into it from both sides.
• Small tributaries feed water into the main stream throughout the mountain valley.
• The Amazon’s tributaries drain water from across the South American continent.
• Several tributaries join the Colorado River as it flows through the Grand Canyon.
• Ancient Rome collected taxes from its tributaries across the empire.
• The conquered territories became tributaries of the expanding kingdom.