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?
nebulous: 1375 – 1425 Late Middle English)
nebula: 1655-65 < Latin
Best Answer
These words come from Latin nebula. Both nebula and nebulosus ("nebulous") existed in classical Latin. In the Middle Ages, anyone who could write was likely to know Latin.
That is why writers freely borrowed such Latin and French words as they saw fit: it is very well possible that the English derivation of nebulosus was used before that of nebula. However, that doesn't tell us much, because no doubt those writers knew both Latin words and had both in mind. Latin and English together formed a large mass (or mess) from which a writer could take any word he needed, Latin being used mostly where an English word was lacking, or where a high register was desired.
In addition, I believe the word nebula was first borrowed as nebule, attested from ca. 1420, according to the Oxford English Dictionary. Note that nebule originally just meant cloud, fog, mist—nothing specifically scientific. It is used figuratively here:
This comes quite close to the earliest attested date for nebulous, ca. 1386:
Though by no means necessary, it is also very well possible that nebule was used in English writing some time before nebulous/nebulus but in a lost document.