Formal:
* Panimula: This is the most common and direct translation, meaning "introduction."
* Pasimula: This also means "beginning" or "start."
* Pamagat: This translates to "title" but can also be used to refer to the introductory part of a document.
Informal:
* Panimulang bahagi: This translates to "introductory part" and can be used in a more casual setting.
* Unang bahagi: This means "first part" and can be used to refer to the preamble of a document.
The best translation for "preamble" in Tagalog will depend on the specific context and the level of formality required.
For example, if you are talking about the preamble of a constitution, you would use a more formal translation like Panimula or Pasimula. If you are talking about the introduction to a story, you could use a more informal translation like Panimulang bahagi.