Thirteenth (adjective)

1. Being the ordinal form of the number thirteen.
2. Coming after the twelfth and before the fourteenth in position or time.

Origin:

Derived from the ordinal form of the number 13, which comes from the proto-germanic *þritiun.

Examples:

1. The thirteenth day of the month.
2. He was the thirteenth person in line.
3. The thirteenth century was a time of great change.
4. The thirteenth chapter of the book.
5. He was the thirteenth player selected in the draft.