Crossword Genius

Colourful type from major hospital spoke out with intelligence (4,6)

Ross

I believe the answer is:

grey matter

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

I cannot understand how the rest of the clue works.

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(Other definitions for grey matter that I've seen before include "Intelligence; the brain" , "intellectual capacity?" , "Issue lacking clear boundaries" , "stuff in the head" , "Brains" .)

I've seen this clue in the Irish Times.
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