Someone disembarking from the craft (7)

I believe the answer is:

lighter

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'the craft' is the definition.
(lighter is a kind of craft)

I cannot understand how the rest of the clue works.

(Other definitions for lighter that I've seen before include "Less weighty" , "less tonnage" , "Smoker's implement" , "Goods barge" , "Vessel" .)

I've seen this clue in the Evening Standard.

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