Matron's broken a crossbeam (7)

I believe the answer is:

transom

'a crossbeam' is the definition.
(I've seen this before)

'matron's broken' is the wordplay.
'broken' indicates an anagram.
'matrons' anagrammed gives 'TRANSOM'.

(Other definitions for transom that I've seen before include "Lintel" , "Bar above window or door" , "Strengthening crossbar" , "Crossbar over a window" , "timber for doorframe" .)

I've seen this clue in The Daily Express.

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