Crossword Genius

Turn over hat dimensions (7)

Ross

I believe the answer is:

capsize

'turn over' is the definition.
(capsizing is a kind of turning over)

'hat dimensions' is the wordplay.
'hat' becomes 'cap' (I've seen this before**).
'dimensions' becomes 'size' (I've seen this before).
'cap'+'size'='CAPSIZE'

(Other definitions for capsize that I've seen before include "Upset" , "Turn so that keel faces upwards" , "Of boat, turn turtle" , "Overturn (a boat)" .)

I've seen this clue in The Telegraph.
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