Crossword Genius

Part of group, including FBI agents (7)

Ross

I believe the answer is:

segment

'part' is the definition.
(I know that segment is a type of part)

'group including fbi agents' is the wordplay.
'group' becomes 'set' (both can mean a collection).
'including' means one lot of letters goes inside another.
'fbi agents' becomes 'g-men' ('G-man' can be a synonym of 'fbi agent').
'set' placed around 'gmen' is 'SEGMENT'.

'of' is the link.

(Other definitions for segment that I've seen before include "Part of, eg, an orange" , "Part of a circle cut off by a chord" , "(Divided-up) part" , "Piece of an orange" , "Section of a circle" .)

I've seen this clue in The Guardian.
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