In a way that happens by chance or luck; by fortunate accident rather than planning.
From 'fortuitous' (Latin 'fortuitus,' from 'fors' meaning 'chance' or 'fortune') plus the '-ly' adverb suffix. The word entered English in the 1600s to describe accidental good luck.
People often use 'fortuitously' and 'fortunately' interchangeably, but linguists care about the difference—'fortuitously' means pure chance (good or bad!), while 'fortunately' specifically means it turned out well. It's a distinction that keeps philosophers happy!
Complete word intelligence in one call. Free tier — 50 lookups/day.