The name Caitriona is a girl's name of Gaelic, Scottish origin meaning "pure". Caitriona and is often added to lists like Names That Mean Pure and discussed in our forums with posts like "Girls Makeover - Two Middles".
From the experts:
Both Caitriona and Catriona are commonly heard in Scotland and Ireland. The name was brought to Ireland by the Anglo-Normans, and is the source of nicknames Cait, Caitin, Caitlin and Triona. Actress Caitrona Balfe has gained recognition for her role on Outlander. Pronunciation is like the more phonetic Katrina.