numeric
The native Japanese numeral for nine, used for counting general items with the つ counter.
りんごを九つください。
Please give me nine apples.
娘は今年で九つになります。
My daughter will be nine years old this year.
noun
twelve o'clock (old time system)
In the old Japanese temporal hour system, 九つ corresponded to the modern twelve o'clock (noon or midnight). This usage is now historical and rarely encountered outside explanations of the old system.
江戸時代には、正午を「九つ」と呼んだ。
In the Edo period, noon was called 'kokonotsu'.