The date a contract ends. Indian index options settle in cash against a level computed from a window near the close on that date, so no single print decides what every contract pays. Days to expiry is the number this desk sorts every chain on, because the bucket names it could have used sort in the wrong order.
Mayawhat these words mean
Maya reads the desk’s written explainers and the glossary. She holds no market data at all, so she can say what a thing is and cannot say what it is doing today.