1. Plural of intercalary; days, months, or other time units inserted into a calendar to keep it synchronized with the solar year.
Usage: technical; chiefly historical or astronomical
2. In botany, tissues or structures inserted or growing between other parts.
Usage: technical; botanical

Examples

• The ancient Romans used intercalaries to adjust their calendar.
• February 29 is one of the most familiar intercalaries in the modern Gregorian calendar.
• Leap years contain intercalaries that prevent the calendar from drifting relative to Earth's orbit.
• In plant growth, intercalaries allow stems to elongate between nodes.
• The Julian calendar introduced intercalaries to address the discrepancy between the calendar year and the solar year.