For age:
* Mukhula: This is the most common term for "old" when referring to a person's age.
* Mukulu: This is another term for "old," but it can also mean "big" or "great."
For something that is not new:
* Kulu: This refers to something that is old, worn out, or used.
* Mung'ombe: This is a more informal term for something that is old or worn out, literally meaning "cattle."
* Kubaba: This term means "to become old" or "to age."
For a concept of being old:
* Bukhula: This refers to the state of being old.
The most appropriate term will depend on the specific context and nuance you are trying to convey.