Strange sins or original one (13)

I believe the answer is:

transgression

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'one' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.

'strange sins or original' is the wordplay.
'original' is an anagram indicator.
'strange'+'sins'+'or'='strangesinsor'
'strangesinsor' is an anagram of 'TRANSGRESSION'.

Can you help me to learn more?

(Other definitions for transgression that I've seen before include "Wrong" , "Wrongdoing" , "Infringement; sin" , "something bad going on?" , "Offence" .)

I've seen this clue in The Times.

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