The most common and most likely answer to this crossword clue is the 5 letter word TORCH
I've seen this crossword clue in The Guardian
T
O
R
C
H
More clues leading to the result TORCH
- Light Muscat or Chablis bottles
- Light rent reduced with support of church
- On hill, check flashlight
- Church on rocky outcrop set ablaze
- Chapter in scripture for a source of illumination
- Actor chooses to conceal lamp
- Burn chunk of peat or charcoal
- It’s light and carried for love
- Light resistance, caught in flipping hot surroundings
- Light from church beyond hill
Buddy explains!

The straight part
We know that "light" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case light = torch.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 TORCH mean?
TORCH noun- A stick with a flame on one end, used chiefly as a light source; a similarly shaped implement with a replaceable supply of flammable material.
- A portable light source powered by electricity; a flashlight.
- An arsonist.
- A blowtorch or oxy-gas torch.
- To set fire to, especially by use of a torch (flaming stick).