* It's a misspelling. Did you mean a similar-sounding word?
* It's a regional dialect word. If you know where you heard it, that might help narrow down the meaning.
* It's a made-up word. Perhaps it's a nickname, a term of endearment, or a word used in a specific context.
To help me understand what you mean, please provide more context:
* Where did you hear this word?
* What was the situation?
* What did the speaker intend to convey?
With more information, I might be able to help you figure out the meaning of "laluu".