Chosen or chooser (7)

I believe the answer is:

elector

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'chooser' is the definition.
Both the definition and answer are singular nouns.
Perhaps you can see an association between them that I can't see?

'chosen or' is the wordplay.
'chosen' becomes 'elect' ('elect' as an adjective can mean chosen).
'elect'+'or'='ELECTOR'

Can you help me to learn more?

(Other definitions for elector that I've seen before include "One has a legal right to vote" , "might he make one cross?" , "one given a choice" , "Germanic prince" , "One exercising suffrage" .)

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

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