Measure beat in heart (10)

I believe the answer is:

centimetre

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'measure' is the definition.
(centimetre is a kind of measure)

'beat in heart' is the wordplay.
'beat' becomes 'time' (I can't justify this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'heart' becomes 'centre' (synonyms).
'time' inserted into 'centre' is 'CENTIMETRE'.

Can you help me to learn more?

(Other definitions for centimetre that I've seen before include "not giving an inch then?" , "Short distance" , "About four tenths of an inch" , "Measure" , "Short length" .)

I've seen this clue in The Telegraph and The Times.

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