Formal:
* Kapatid: This is the most general term for sibling, and can refer to both brother and sister.
* Kuya: This is used for an older brother.
* Ate: This is used for an older sister.
Informal:
* Pare: This is a casual term for a close friend, but can also be used to address a brother.
* Bro: This is an English word that is commonly used in Filipino.
Specific terms:
* kapatid na lalaki: This literally means "male sibling" and is used when you need to specify that you're talking about a brother.
* kapatid sa ama: This means "brother by the same father" and is used when you want to distinguish between half-brothers and full brothers.
* kapatid sa ina: This means "brother by the same mother" and is used when you want to distinguish between half-brothers and full brothers.
The best way to choose the right word depends on the situation. If you're speaking to someone you know well, you can use informal terms like "pare" or "bro". If you're speaking to someone you don't know well, or if you're being formal, it's best to use a more formal term like "kapatid" or "kuya".