Q: How many four letter words exist in the English language? (excluding curse words.)
A: I did not exclude curse words because that can differ based on region, era, and cultural background.
With 26 letters in the English alphabet, there are 45,6976 possible 4 letter combinations (26*26*26*26). Out of these, only 2746 are not words. That means the remaining 45,6976 are words.
List of non-words with 4 letters can be found here.
Question found on Answerbag.com. Answer is mine.