The most common and most likely answer to this crossword clue is the 10 letter word IONOSPHERE
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More clues leading to the result IONOSPHERE
- Spacecraft may enter it: I soon changed pressure at this point
- Poison working at this point? It’s up in the air
- See her moving with no poise in a high place very few get to
- Poison spread to this place — it’s in the air
- Poor hen is somehow England’s top layer
- Highly reflective coating?
- Poison diffused at this point somewhere up high
Buddy explains!

The straight part
We know that "it’s in the air" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it’s in the air = ionosphere.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 IONOSPHERE mean?
IONOSPHERE noun- The part of the Earth's atmosphere beginning at an altitude of about 50 kilometers (31 miles) and extending outward 500 kilometers (310 miles) or more.
- The similar region of the atmosphere of another planet.