Factory functions (5)

I believe the answer is:

works

I believe this is a double definition.

'factory' is the first definition.
(eg a steel works)

'functions' is the second definition.
('work' can be a synonym of 'function')

(Other definitions for works that I've seen before include "Factory; has a job" , "Acts: the > opera" , "Functions" , "Employs physical or mental effort" , "Plants; operates" .)

I've seen this clue in The Telegraph.

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