Rita altered a capital investment (5)

I believe the answer is:

tiara

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'capital investment' is the definition.
Although both the answer and definition are singular nouns, I can't understand how one could define the other.

'rita altered a' is the wordplay.
'altered' is an anagram indicator.
'rita' is an anagram of 'tiar'.
'tiar'+'a'='TIARA'

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(Other definitions for tiara that I've seen before include "Small crown" , "High diadem" , "Jewelled head-ornament" , "Jewelled head band" , "Ornamental head gear" .)

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

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