1. The head or enlarged end of a bolt, typically rounded or hexagonal in shape.
Usage: technical; commonly used in engineering and construction
2. A rounded glass vessel with a long neck, used in laboratories for distillation.
Usage: chemistry; also called a round-bottomed flask

Examples

• The bolthead was stripped, so we had to replace the entire bolt.
• Make sure the bolthead is tight enough to prevent the joint from loosening.
• The chemist carefully heated the liquid in the bolthead over a Bunsen burner.
• A bolthead with a hexagonal shape is easier to grip with a wrench.
• The bolthead on the engine block had corroded after years of exposure to moisture.