Crossword Genius

Some had a tumble and that's a fact (5)

Ross

I believe the answer is:

datum

'that's a fact' is the definition.
(singular form of 'data')

'some had a tumble' is the wordplay.
'some' says the answer is hidden in the clue (some parts of the word are used).
'DATUM' is hidden within 'had a tumble'.

'and' is the link.

(Other definitions for datum that I've seen before include "Something given" , "Bit of dope" , "Given piece of information" , "Given fact" , "One item of information" .)

I've seen this clue in The Globe and Mail.
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