1. to insert (something, such as a day or month) into a calendar
Usage: technical
2. to insert or introduce between or among existing elements
Usage: formal

Examples

• The calendar intercalates an extra day every four years.
• February 29th is intercalated during leap years.
• The author intercalates personal anecdotes throughout the historical narrative.
• The geologist noted how sedimentary layers intercalate with volcanic deposits.
• The editor intercalates footnotes to clarify complex passages.
• Ancient calendars often intercalated months to align with seasonal cycles.