The most common and most likely answer to this crossword clue is the 5 letter word ARGON
I've seen this crossword clue in The Times
A
R
G
O
N
More clues leading to the result ARGON
- Element damaging organ
- Element in technical speech Jack ignored
- Organ’s playing — a gas!
- Inert substance oceanographer carries back
- Greek festival inspires king – it’s something in the atmosphere
- Gas power almost failed — almost
- An element in Bihar go native
- Element of technical language judge avoided
- Old ship with nitrogen gas
- Primarily another rare gas
Buddy explains!
The straight part
We know that "Inert substance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case inert substance = argon.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 ARGON mean?
ARGON noun- The chemical element (symbol Ar) with an atomic number of 18. The third most abundant gas in the Earth's atmosphere, it is a colourless, odourless, inert noble gas.
- A single atom of this element.