Major city investment (7)

I believe the answer is:

capital

I believe this clue is a double definition.

'major city' is the first definition.
(I've seen this before)

'investment' is the second definition.
(I've seen this before)

(Other definitions for capital that I've seen before include "Cardinal; splendid; assets" , "source of profit" , "A great city - that's fine" , "Seed money" , "A big letter, or a big city" .)

I've seen this clue in The Guardian and The Globe and Mail.

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