The most common and most likely answer to this crossword clue is the 8 letter word SUNLIGHT
I've seen this crossword clue in The Guardian
S
U
N
L
I
G
H
T
More clues leading to the result SUNLIGHT
- Ray helps to make this newspaper entertaining
- Natural illumination in view across one French lake
- Paper not serious, but it’s illuminating
- Illumination provided by peace keepers during cut
- Foreign article held by small beams
- Illumination needed, peacekeepers being involved in insult
- What’s illuminating, naturally, in paper, and easy to pick up
- Star is not heavy but will still give you a tanning
- Minor, around one might wake you up
- UN held in disregard in the daytime
Buddy explains!

The straight part
We know that "it’s illuminating" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it’s illuminating = sunlight.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SUNLIGHT mean?
SUNLIGHT noun- All the electromagnetic radiation given off by the Sun, especially that in the visible spectrum that bathes the Earth.
- Brightness, hope; a positive outlook.
- To work on the side (at a secondary job) during the daytime.
- The time of day when the sun appears above the eastern horizon.
- The change in color of the sky at dawn.
- Any great awakening.