1. having three angles or corners; triangular in shape
Usage: geometry
2. relating to or having a crystal system characterized by three equal axes intersecting at equal angles
Usage: crystallography

Examples

• The trigonal prism has three rectangular faces.
• Quartz crystals belong to the trigonal crystal system.
• The architect designed a trigonal courtyard for the building.
• Students learned to identify trigonal shapes in geometry class.
• The mineral specimen displayed perfect trigonal symmetry.
• Trigonal bipyramidal is a common molecular geometry.