It is possible that:
* It's a misspelling: There might be a similar word you are thinking of, and you've made a typo.
* It's a regional dialect or slang: It might be a word used in a specific place or community.
* It's a made-up word: Maybe it's part of a fictional story or online game.
To help me understand what you mean, please provide:
* Context: Where did you hear or see this word? What was the situation?
* Any other information: Do you know what language it might be from? Any other clues?
Once I have more information, I can help you figure out the meaning of "ouala."