Willie Cauley-Stein is now officially Willie Cauley-Stein.

The former Kentucky Wildcats star, who has declared himself eligible for next month's NBA draft, was actually born Willie Durmond Cauley Jr. But with his father largely absent from his life he adopted the surname Cauley-Stein to honor his mother, Marlene Stein. That's how he's been known during his time at Kentucky.

The 21-year-old made the name official recently in a filing at the Probate Division of the Fayette District Court in Kentucky.

While he was at it, Cauley-Stein added "Trill" as his middle name. Trill, according to Urban Dictionary, is "an adjective used in hip-hop culture to describe someone who is considered to be well respected, coming from a combination of the words 'true' and 'real'."

"Trill is the "nickname his 'boys' call him," Marlene Stein told reporters.

Even though he submitted the paperwork at a courthouse, Cauley-Stein really made a name for himself on the basketball court. The 7-footer led Kentucky to an undefeated regular season and a trip to the Final Four. A former high school football star, Cauley-Stein was voted the SEC's Defensive Player of the Year.

According to most mock drafts, Cauley-Stein is expected to be selected in the top 10 picks of this year's NBA draft.

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