Russian vernacular for penis, i.e., "prick" or "dick" or "cock." One of the most widely-used words in Russian. Sometimes transliterated "khui."
The similarity of the Americanism "hooey" (as in "that's a lot of hooey") brings a smile to the Russian who hears it for the first time.
Vot tebe khuy! (there's a real prick for you)