The most common and most likely answer to this crossword clue is the 9 letter word ENERGISED
I've seen this crossword clue in The Daily Telegraph
E
N
E
R
G
I
S
E
D
More clues leading to the result ENERGISED
- With queen’s entrance, intended briefly to rise with new vigour
- Fresh greens I’d eat at first, given vitality
- Ready for anything — seeing red when disturbed
- Excited Greens die out
- Stimulated and seeing red when riled
- Enthusiastic doctor resigned after end of case
- Gave zip to English fashion designer
- Fired up – what’s that when cooking in degrees?
- Fired up, seeing red, going crazy
Buddy explains!

The straight part
We know that "Fired up" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fired up = energised.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 ENERGISED mean?
ENERGISED adjective- Alternative spelling of energized
- To invigorate; to make energetic.
- To supply with energy, especially electricity; to turn on power to (something).
- To use strength in action; to act or operate with force or vigor; to act in producing an effect.