Insect in Spooner's large jug, empty (9)

I believe the answer is:

dragonfly

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'insect' is the definition.
(dragonfly is a type of insect)

I can't explain the remainder of the clue.

(Other definitions for dragonfly that I've seen before include "creature!" , "Insect with two pairs of transparent wings" , "it wings along" , "Large winged insect" , "Large hovering insect" .)

I've seen this clue in The Telegraph.

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