Establish a group (3)

I believe the answer is:

set

I believe this is a double definition.

'establish' is the first definition.
(I know that set is a more specific form of the action establish)

'a group' is the second definition.
(I know that set is a type of accumulation)

(Other definitions for set that I've seen before include "Gel; group" , "'Put, place or fix in position (3)'" , "Group; hard" , "Cake < , plonk < , something served" , "Determined or congealed" .)

I've seen this clue in The Irish Independent.

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