Fantasising (8)

I believe the answer is:

dreaming

'fantasising' is the definition.
(I've seen this before)

This is all the clue.

(Other definitions for dreaming that I've seen before include "Having fantasies about Niger Dam" , "Fantasising" , "form of idealism?" , "'I'm ... of a white Christmas' (song)" , "In reverie" .)

I've seen this clue in the Sydney Morning Herald and the Evening Standard.

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