Underworld Society brought up ghost (5)

I believe the answer is:

shade

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

'ghost' is the definition.
(I know that ghost can be written as shade)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for shade that I've seen before include "Relative darkness" , "Area sheltered from the sun" , "Slight colour difference" , "blind" , "See 15" .)

I've seen this clue in The Independent.

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