Maddy ranks at #722 with 165 entries, registered female. The name is the casual diminutive of Madeline and Madison, and on a pet registry it functions as the nickname-as-formal-name pattern: the household always called the dog Maddy, and the formal license simply records what the family actually says.
The diminutive-as-formal-name pattern
Maddy sits with Maddie, Madi, and Mads in the cluster of Madeline-Madison nickname spellings on the licensing chart. The Y-ending version reads as slightly more old-fashioned and warm than the IE-ending Maddie, and the spelling choice usually reflects the household's habitual preference rather than a deliberate distinction.
The Euphoria overlay and pop-culture refresh
For younger owners, Maddy carries an Euphoria overlay through the character Maddy Perez (played by Alexa Demie), which has refreshed the name for Gen Z viewers since 2019. The pet-naming wave from this overlay has been modest but real, particularly in households where the owner came of age watching the show.
Sound and breed lean
Two syllables, front-stressed (MAD-ee), hard M opening, soft trailing vowel. The shape recalls cleanly across voice ranges and reads warmly. The name lands across breed types without strong concentration: Golden Retrievers, Labradors, mixed-breed rescues, and small companion breeds. The human Maddy page shows steady modern SSA presence as Madeline and Madison both remain popular human formal names.