Formal:
* Tiyo: This is the most common and formal way to say "uncle." It's used for any uncle, regardless of the relationship to their spouse.
* Tio: This is a more Spanish-influenced term and is also used formally.
Informal:
* Tito: This is a more familiar and informal way to say "uncle." It's commonly used for uncles who are close to the speaker.
* Tita: This is used for the uncle's wife, who is also considered an "aunt" in this context.
Other considerations:
* Relationship to the speaker's parents: If the uncle is a brother of the speaker's father, he might be called "Kuya" (older brother).
* Relationship to the speaker's spouse: If the uncle is related to the speaker's spouse, he might be addressed by their relationship to the spouse (e.g., "Uncle of my wife").
Example:
* "My tiyo lives in the Philippines." (Formal)
* "I'm going to visit my tito this weekend." (Informal)
The specific term you use will depend on the context and your relationship with the person.