The most common and most likely answer to this crossword clue is the 8 letter word NITROGEN
I've seen this crossword clue in Independent
N
I
T
R
O
G
E
N
More clues leading to the result NITROGEN
- Element in ringtone that's phony?
- New ringtone is a gas
- Gas ring, note, for repair
- Element identified by Italian fellow endlessly in news
- Element of ringtone jangled
- Ringtone destroyed much of the atmosphere
- . Gas that appears first in Newcastle
- Ring tone playing part of air
- Changed ringtone element
- Get iron transmuted to new element
Buddy explains!

The straight part
We know that "part of air" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of air = nitrogen.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 NITROGEN mean?
NITROGEN noun- The chemical element (symbol N) with an atomic number of 7 and atomic weight of 14.0067. It is a colorless and odorless gas.
- Molecular nitrogen (N2), a colorless, odorless gas at room temperature.
- A specific nitrogen within a chemical formula, or a specific isotope of nitrogen