Is the first murder victim a girl? (6)

I believe the answer is:

isabel

'a girl?' is the definition.

'is the first murder victim' is the wordplay.
'the first murder victim' becomes 'Abel' (Abel was murdered by his brother Cain in the Bible).
'is'+'abel'='ISABEL'

(Other definitions for isabel that I've seen before include "Miss" , "Girl's name" , "- Allende, Chilean novelist" , "Abseil with confused girl" , "Drab" .)

I've seen this clue in The Guardian, The Telegraph and The Globe and Mail.

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