The most common and most likely answer to this crossword clue is the 5 letter word GLARE
G
L
A
R
E
Buddy explains!
The straight part
We know that "Term for excessive luminance involved with 60% of argon" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case term for excessive luminance involved with 60% of argon = glare.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 GLARE mean?
GLARE noun- An intense, blinding light.
- Showy brilliance; gaudiness.
- An angry or fierce stare.
- A call collision; the situation where an incoming call occurs at the same time as an outgoing call.
- A smooth, bright, glassy surface.
- A viscous, transparent substance; glair.
- To stare angrily.
- To shine brightly.
- To be bright and intense, or ostentatiously splendid.
- To shoot out, or emit, as a dazzling light.
- (of ice) smooth and bright or translucent; glary