1. the quality or state of being completely sealed so that air cannot pass through

Examples

• The airtightness of the container kept the food fresh for weeks.
• Building codes require testing for airtightness in new construction.
• The spacecraft’s airtightness is critical for crew safety.
• We checked the airtightness of the vacuum chamber before the experiment.
• Poor airtightness in windows can increase heating costs.
• The jar’s airtightness prevented the spices from losing their flavor.