Here's a breakdown of the individual words:
* Rehu: This word doesn't have a common meaning in Māori. It could be a variation of "rehua" which means "star" or "planet".
* Tai: This word means "tide" or "ocean."
Without context, it's difficult to understand the intended meaning of "rehu tai".
Could you provide more context about where you heard or saw this phrase? For example, was it in a song, poem, or conversation? This information would help determine the intended meaning.