A little room in port (4)

I believe the answer is:

aden

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'port' is the definition.
(port in Yemen)

'a little room' is the wordplay.
'little room' becomes 'den' (den is a kind of room. I am not sure about the 'little' bit.).
'a'+'den'='ADEN'

'in' acts as a link.

Can you help me to learn more?

(Other definitions for aden that I've seen before include "Port city of Yemen" , "Yemen's chief port" , "Yemeni gulf" , "Dean is in the Yemen, strangely" , "Commercial capital of Yemen" .)

I've seen this clue in the Evening Standard.

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