“9th” (ninth) means:

• The ordinal form of 9, showing position in a sequence.
  • Example: He finished 9th in the race = he came in position number nine.
• It can also refer to:
  • The 9th day of a month (e.g., July 9th)
  • The ninth item, rank, or place in an ordered list

In short, it means number nine in order or rank.