The most common and most likely answer to this crossword clue is the 7 letter word ZEALOTS
I've seen this crossword clue in The Guardian
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More clues leading to the result ZEALOTS
Buddy explains!
The straight part
We know that "Enthusiasts" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case enthusiasts = zealots.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 ZEALOTS mean?
ZEALOTS noun- One who is zealous, one who is full of zeal for his own specific beliefs or objectives, usually in the negative sense of being too passionate; a fanatic
- A member of a radical, warlike, ardently patriotic group of Jews in Judea, particularly prominent in the first century, who advocated the violent overthrow of Roman rule and vigorously resisted the efforts of the Romans and their supporters to convert the Jews.
- A member of an anti-aristocratic political group in Thessalonica from 1342 until 1350.