He keeps far too much to himself (5)

I believe the answer is:

miser

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'he keeps far too much to himself' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.

This is all the clue.

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(Other definitions for miser that I've seen before include "One's tight" , "screw" , "Penny-pinching person like Scrooge" , "not a spendthrift" , "Wealth hoarder" .)

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

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