Solitary individual, I must bring two sides together (5)

I believe the answer is:

loner

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

I cannot understand how the rest of the clue works.

(Other definitions for loner that I've seen before include "Non-conformist" , "Recluse" , "Solitary person" , "Isolated person" , "No mixer" .)

I've seen this clue in The Times.

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