Dockland structure rather black? (5)

I believe the answer is:

jetty

I'm a little stuck... Click here to teach me more about this clue!

This clue might be a double definition.

'dockland structure' is the first definition.
'jetty' can be an answer for 'structure' (jetty is a kind of structure). I am not certain of the 'dockland' bit.

'rather black?' is the second definition.
'jetty' can be an answer for 'black?' (thesaurus). I'm not certain of the 'rather' bit.

Can you help me to learn more?

(Other definitions for jetty that I've seen before include "Quay" , "Dock" , "Small landing stage" , "Wharf" , "Pier - landing stage" .)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.