Jack

Jack is a medieval English diminutive of John, which comes from the Hebrew Yochanan meaning "God is gracious." For centuries it was so common in England that "Jack" became a generic term for any man. The name has since shed that anonymity entirely and now carries associations with quick intelligence, irreverence, and a certain roguish charm.

Jack lands at #27 among the most popular US pet names, with over 2,350 companions sharing it. It is one of those names that feels both timeless and current — rooted in history but never dusty. Jack suits companions who are alert, quick-witted, and endlessly entertaining. The single syllable packs a surprising amount of personality, cutting through the noise of a busy household with easy authority. Its consistent popularity across human and pet naming speaks to something deeply satisfying about how it sounds.