Son, fast mover, finding allotment (5)

I believe the answer is:

'allotment' is the definition.
(I know that share is a type of allotment)

'son fast mover' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'fast mover' becomes 'hare' (hares run fast).
's'+'hare'='SHARE'

'finding' acts as a link.

(Other definitions for share that I've seen before include "Divide out, apportion" , "Distribute" , "Give portion to others" , "Cut" , "Cutting blade" .)

I've seen this clue in The Times.

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