Variant of Xenia, from Greek 'xenia' meaning hospitality or welcoming stranger.
Senia most likely descends from Xenia, the ancient Greek name built on the word xenos (ξένος), meaning stranger, guest, or foreigner — and from that, the virtue of hospitality shown to strangers. Xenia was more than a personal value in ancient Greece; it was a sacred social institution, the guest-friendship that bound host and visitor in mutual obligation and protected travelers across a world without hotels.
Zeus himself was invoked as Xenios, the protector of guests, and violations of xenia — like Paris's seduction of Helen while a guest of Menelaus — were understood as cosmic offenses that could start wars. The name traveled through Eastern Orthodoxy as a saint's name — Saint Xenia of Saint Petersburg is one of the most beloved Russian saints, an 18th-century holy fool who gave away all her possessions after her husband's death and spent decades wandering the city in his old uniform, said to perform miracles. The name spread throughout Slavic Europe in numerous forms and diminutives, with Senia emerging as a softer, more melodic variant suited to Southern and Eastern European naming traditions.
In the broader Western naming world, Senia remains rare enough to feel genuinely distinctive, yet its roots in one of classical antiquity's most beautiful concepts — the ethics of welcome, the sacred duty toward the stranger — give it remarkable depth. Parents who discover Senia often find it strikes an exact balance between the familiar and the foreign, which is, perhaps fittingly, exactly what the name itself has always meant.