While looking up
nebulous, I noticed the origin of the word is dating back to 14th century. Surprised since the nebulae wasn't discovered at that time, I checked
nebula to find that its origin dates to 17th century. Given nebulous means nebula-like, it seems inconsistent that it enters the dictionary before its derivative.
It's obvious that
nebula with its Greek/Latin root existed long before 17th century. But could
nebulous have been used without
nebula not even being mentioned for 3 centuries?
Am I missing a point? Or is the dictionary wrong?
Or should we take these as non-definitive dates which just represent the first written occurrence of the word?