The most common and most likely answer to this crossword clue is the 9 letter word FEROCIOUS
I've seen this crossword clue in The Guardian
F
E
R
O
C
I
O
U
S
More clues leading to the result FEROCIOUS
Buddy explains!

The straight part
We know that "Savage" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case savage = ferocious.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 FEROCIOUS mean?
FEROCIOUS adjective- Marked by extreme and violent energy.
- Extreme or intense.