1. a resinous substance collected by bees from tree buds and used to seal cracks in their hives

Examples

• The bees used propolis to fill gaps in the hive walls.
• Propolis has antimicrobial properties that help protect the colony.
• Beekeepers often find propolis stuck to their hive tools.
• The dark, sticky propolis made it difficult to separate the frames.
• Some people use propolis as a natural health supplement.
• The bees collected propolis from the poplar trees nearby.