Rudy

Rudy is a familiar form of Rudolf or Rudolph, a Germanic name combining elements for fame and a wolf. It has also become an independent given name, so the longer form is not required. The animal element belongs to the older compound rather than implying a particular character or temperament.

The film Rudy gives the name a sporting association, while Rudy Steiner is a memorable character in The Book Thief. Rudi is a close spelling alternative. Using Rudy directly preserves the two-syllable short form in every setting, while Rudolf or Rudolph makes the older name-family connection more explicit on official records.