The most common and most likely answer to this crossword clue is the 5 letter word RABID
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More clues leading to the result RABID
- Fanatical attack captures bishop
- Wild call by card player after ace and king turned over
- Fanatical attack involving bishop
- Fanatical incursion capturing British
- Fanatical bishop taking part in attack
- Hydrophobic sailor with freehold?
- Ferocious attack overwhelms British
- Mad British in aggressive action
- Army tender out of control
- Frenetic onslaught seizes bomber
Buddy explains!

The straight part
We know that "Zealous" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case zealous = rabid.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 RABID mean?
RABID noun- A human or animal infected with rabies.
- Someone who is fanatical in opinion.
- Affected with rabies.
- Of or pertaining to rabies, or hydrophobia.
- Furious; raging; extremely violent.
- Very extreme, unreasonable, or fanatical in opinion; excessively zealous.