The most common and most likely answer to this crossword clue is the 3 plus 4 letter word ARC LAMP
A
R
C
L
A
M
P
More clues leading to the result ARC LAMP
- Headings of analyst’s ring binder that should shed some light
- A vice securing top of rotating light
- Under vehicle with roof sheared off, securely grip light
- Vice beneath a river light
- Device used to fix electric light
- Light hair regularly requires a grip
- Gunners returned to fix light
- A reader’s first vice — one that provides illumination
- Area only half visible? Fix a light
- A bracket holding right light source
Buddy explains!
The straight part
We know that "light source" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case light source = arc lamp.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.