What does high monocyte % mean in blood?

Nothing: I often wish labs wouldn't even report the percentages. An absolute monocyte count over 600 will raise eyebrows if there's any suspicion of tb, sarcoid, deep fungal infection -- but it's only one tiny clue. The counts and percentages fluctuate wildly from day to day and even hour to hour. Ignore it -- you're not just a bunch of numbers -- and ask, "how do I feel?".