Uhnykah is a term used to describe a "whore," male or female, who interacts with people of a more intellectual account. Therefore, by doing this, they feel they conduct a more sophisticated nature, while erotically pleasuring the "superiors" of that group.
"Did you hear what that slutty Uhnykah said? She was all, 'My boobs are mass times length. We should meet up later for a study session.' Ew. What a skank."