Here are some possibilities:
* "Coo-yah": This is a common exclamation in Jamaican patois, often used to express excitement, encouragement, or approval. It's similar to "hooray" or "yeah!"
* "Cooyah" as a mispronunciation: It's possible you've heard a word like "coya" or "coyaba" mispronounced. "Coya" can mean "shy" or "cowardly," while "coyaba" refers to a type of tropical fruit.
If you can provide more context or an example of how you've heard the word used, I may be able to give a more accurate answer.