* Translation (most common and general)
* Transliteration (specifically for converting characters from one writing system to another)
* Interpretation (when referring to conveying meaning, not just literal words)
The best translation depends on the context. Can you give me more context about what "alih bahasa" refers to? For example, are you talking about:
* Translating a document from Indonesian to English?
* Converting Indonesian names into English spelling?
* Explaining the meaning of an Indonesian idiom in English?
Knowing the context will help me give you the most accurate translation.