* "Old man" or "grandfather" - This is the most common meaning of "baba" in Japanese. It's a very informal and sometimes even derogatory term for an elderly man.
* "Old woman" or "grandmother" - While less common than the previous meaning, "baba" can also be used to refer to an elderly woman, also in a casual and sometimes disrespectful way.
* "Fool" or "idiot" - In some contexts, "baba" can be used as a slang term for a stupid or foolish person, regardless of age or gender.
It's important to note that using "baba" to refer to someone can be considered rude, especially if you're not close to the person. It's generally best to use more respectful terms like "ojīsan" (old man) or "obāsan" (old woman) if you need to refer to an elderly person.
If you're unsure of the context or the speaker's intentions, it's always best to ask for clarification.