Some fancy an ideal poison (7)

I believe the answer is:

cyanide

'poison' is the definition.
(thesaurus)

'some fancy an ideal' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'CYANIDE' is hidden in the letters of 'fancy an ideal'.

(Other definitions for cyanide that I've seen before include "Nice day (anag) - poison" , "Extremely poisonous salt" , "Highly toxic substance" , "killer" , "Poisonous compound" .)

I've seen this clue in The Times.

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