Billy

Billy is a diminutive of William, from the Germanic Willahelm composed of wil meaning "will" or "desire" and helm meaning "helmet" or "protection" — so the full meaning is something like "resolute protector." Billy has a classic, approachable American quality, associated with cowboys, outlaws, and ordinary heroes alike. For pets, Billy sheds any pretension and becomes simply a warm, friendly name with good energy — the companion next door, reliable and cheerful, always up for whatever the day brings.

Billy holds #285 on the pet name charts and carries that timeless American friendliness that never goes out of style. Its Germanic roots meaning "resolute protector" are hidden behind a thoroughly casual exterior, but there is often something genuinely protective about companions who bear this name — loyal to their household and attentive to their people. Billy suits a companion who is friendly with everyone but especially devoted to their own family: unpretentious, dependable, and completely at home wherever they are.