Crossword Genius

Sinners actively serve idol (9)

Ross

I believe the answer is:

evildoers

I'm a little stuck... Click here to teach me more about this clue!

'sinners' is the definition.
('evildoer' can be a synonym of 'sinner')

'actively serve idol' is the wordplay.
'serve idol' can be anagrammed to 'EVILDOERS'.
However, I am unsure how the anagram is indicated.

Can you help me to learn more?

(Another definition for evildoers that I've seen is " People acting wickedly".)

I've seen this clue in The Times.
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