It’s nothing, darling (4)

I believe the answer is:

love

I believe this clue is a double definition.

'it's nothing' is the first definition.
(love is zero in tennis)

'darling' is the second definition.
(both are terms of endearment)

(Other definitions for love that I've seen before include "Zero (tennis) four Dn" , "It's nothing in tennis" , "powerful emotion" , "God of 20 Dn" , "1970 film, starring Ali MacGraw and Ryan O'Neal" .)

I've seen this clue in The Times and The Telegraph.

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