Singular ruin (5)

I believe the answer is:

queer

I believe this is a double definition.

'singular' is the first definition.
(I know that singular can be written as queer)

'ruin' is the second definition.
(thesaurus)

(Other definitions for queer that I've seen before include "Strange, odd" , "- - Street" , "Odd; ruin (pitch)" , "Strange, curious" , "Unusual" .)

I've seen this clue in The Telegraph.

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