Shorter iron used in bush (7)

I believe the answer is:

briefer

'shorter' is the definition.
('brief' can be a synonym of 'short')

'iron used in bush' is the wordplay.
'iron' becomes 'fe' (Fe is the chemical symbol for iron).
'used in' is an insertion indicator.
'bush' becomes 'brier' (brier is a kind of bush).
'fe' put within 'brier' is 'BRIEFER'.

I've seen this clue in The Telegraph.

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