Transported in parcel paper say? (4)

I believe the answer is:

rapt

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'transported' is the definition.
(both can mean enchanted or fascinated)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for rapt that I've seen before include "Part (anag.)" , "Enthralled, captivated" , "Fascinated in part" , "Fully engaged" , "Ecstatic in part" .)

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