Sister lied about it being disinfected (10)

I believe the answer is:

sterilised

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'sister lied about it being disinfected' is the definition.
I can't judge whether this definition defines the answer.

'sister lied about' is the wordplay.
'about' is an anagram indicator.
'sister'+'lied'='sisterlied'
'sisterlied' is an anagram of 'STERILISED'.

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(Other definitions for sterilised that I've seen before include "immaculately clean" , "Like theatre equipment" , "Thoroughly cleaned" .)

I've seen this clue in The Irish Times.

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