Arnold appears 74 times at rank 1443 on male pets, applied to dogs by owners who love the Terminator, the Hey Arnold cartoon, or simply want a name that sounds solid and slightly retro without being precious about it. The name has more cultural anchors than its unassuming surface suggests.
The Cultural References
Arnold Schwarzenegger gave the name its action-hero credibility in the 1980s. Arnold from Nickelodeon's Hey Arnold! gave it a cartoon-kid warmth in the 1990s. Arnold the pig from Green Acres planted the name in farm-animal pop culture. The Germanic root means "eagle power" from arn (eagle) and wald (power), adding genuine etymological substance to the name's brawny reputation. The human profile is at /names/arnold.
Breed Fit
Arnold suits large, physically substantial dogs where the Schwarzenegger association has some physical basis — Rottweilers, Great Danes. The pig association from Green Acres also makes it a viable choice for bulldogs with a roly-poly quality owners find endearing.
The Counter-Reading
Arnold occupies a vintage-masculine zone: neither old enough to be definitively retro-chic nor current enough to feel contemporary. It requires the right dog and the right owner to land well. When it does, it lands with conviction and a story worth telling at the dog park.