Thousandth (adjective)

Being one of a thousand equal parts of a whole.

Origin:

From old english þusendþa, equivalent to thousand + -th.

Examples:

1. He was the thousandth person to cross the finish line.
2. She placed a thousandth in the race.
3. He was the thousandth visitor to the exhibit.
4. It was the thousandth time he had told that story.
5. This is the thousandth time I've asked you to be quiet.