Henchy is likely from an Irish surname and family-name tradition, adapted into given-name use.
Henchy is a rare given name with roots as an Irish surname, derived from the Gaelic Ó hAonghusa or anglicised forms of Hennessey-adjacent clans in Munster and Connacht. As a family name it appears in Irish legal and literary history — most notably Justice Seamus Henchy, who served on the Irish Supreme Court in the late twentieth century and was regarded as one of the most intellectually formidable jurists of his era.
The surname carries the particular gravity of the Irish professional classes. Used as a given name, Henchy belongs to the tradition of honouring maternal surnames or beloved relatives by moving a family name into the first-name position — a practice with deep roots in Anglo-Irish and American naming culture. It carries the slightly rakish, old-Dublin energy of names like Fitzwilliam or Cassidy while remaining genuinely uncommon, making it almost impossible to encounter a second Henchy in a classroom.
In the contemporary landscape of vintage revival names, Henchy sits in intriguing territory: familiar enough in sound (the warm "Hen-" opening, the crisp "-chee" close) to feel approachable, yet rare enough to feel like a genuine discovery. It ages well — equally plausible on a toddler, a teenager, and a barrister.