The most common and most likely answer to this crossword clue is the 11 letter word INSPIRATION
I've seen this crossword clue in The Times
I
N
S
P
I
R
A
T
I
O
N
Buddy explains!
The straight part
We know that "Breathtaking idea?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case breathtaking idea? = inspiration.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 INSPIRATION mean?
INSPIRATION noun- The drawing of air into the lungs, accomplished in mammals by elevation of the chest walls and flattening of the diaphragm, as part of the act of respiration.
- A breath, a single inhalation.
- A supernatural divine influence on the prophets, apostles, or sacred writers, by which they were qualified to communicate moral or religious truth with authority; a supernatural influence which qualifies people to receive and communicate divine truth; also, the truth communicated.
- The act of an elevating or stimulating influence upon the intellect, emotions or creativity.
- A person, object, or situation which quickens or stimulates an influence upon the intellect, emotions or creativity.
- A new idea, especially one which arises suddenly and is clever or creative.