Cons one and runs in a tiny fraction of time (10)

I believe the answer is:

nanosecond

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'time' is the definition.
(I have seen 'short time' mean 'nanosecond' so perhaps 'time' could also mean 'nanosecond')

'cons one and runs' is the wordplay.
'runs' indicates an anagram.
'cons'+'one'+'and'='consoneand'
'consoneand' with letters rearranged gives 'NANOSECOND'.

'in a tiny fraction of' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.

Can you help me to learn more?

(Other definitions for nanosecond that I've seen before include "Tiny duration" , "very brief time" , "instant?" , "Only a little flash" , "next to no time!" .)

I've seen this clue in the Sydney Morning Herald.

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