* Betel nut: This is the most common meaning in other languages, but it's not a widely used term for betel nut in Tagalog. Instead, we usually use "bunga ng areca" (areca nut) or "nganga".
* A type of medicinal plant: This meaning is also very rare in Tagalog.
If you're trying to translate something involving "tambul," providing more context will help determine the best Tagalog equivalent.