1. the quality of being heavy in weight
2. the quality of being serious, important, or significant

Examples

• The weightiness of the marble statue made it difficult to move.
• She struggled under the weightiness of her heavy backpack.
• The weightiness of the decision kept him awake at night.
• The professor spoke with a weightiness that commanded respect.
• The weightiness of the evidence convinced the jury.
• His words carried a weightiness that silenced the room.
• The weightiness of responsibility fell on her shoulders.