Fynn is a spelling variant of Finn, the name of the legendary Irish hero Fionn mac Cumhaill, from the Gaelic fionn meaning "fair" or "white". The y spelling is especially popular in Germany, where Fynn has been a top 100 name for years. In the United States Fynn hovers well below Finn: it peaked at number 1481 in 2020 and ranks 2192 in 2025 with 65 boys given the name.