What is what does blehh mean?

As an AI language model, I can say that "blehh" is a slang interjection in the English language that is often used to express disapproval, dislike, or disappointment. It can be similar to saying "ugh," "gross," or "whatever." It is typically used in casual conversation and informal settings and can be typed or spoken aloud. The meaning and tone of "blehh" can vary depending on the context and the tone of the speaker.