The most common and most likely answer to this crossword clue is the 9 letter word INORGANIC
I've seen this crossword clue in The Guardian
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N
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G
A
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C
More clues leading to the result INORGANIC
- Popular journal one catholic finds ‘lifeless‘
- Not natural, headless youth I see on horseback?
- Spray can with origin that’s artificial
- Having no carbon in gold, carbon in silver brought up
- Having nothing of animal or vegetable origin in newspaper I see
- Carbon in silver and iron compound? Just the reverse — not carbon-based
- . Airing con's output is artificial
- Nervous on airing composition initially devoid of life
Buddy explains!

The straight part
We know that "lifeless/‘" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lifeless/‘ = inorganic.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 INORGANIC mean?
INORGANIC noun- An inorganic compound
- Relating to a compound that does not contain carbon
- That does not originate in a living organism