What part of speech is nine?

"Nine" can be a few different parts of speech, depending on its use in a sentence:

* Adjective: Describes a noun, telling us how many. Example: "There were nine kittens playing in the garden."

* Noun: Represents a specific number. Example: "The number nine is considered lucky in some cultures."

* Numeral: Functions as a number, typically used in counting or mathematical operations. Example: "He added nine and five to get fourteen."

So, the specific part of speech of "nine" depends on its context.