Possibly untie but here join together (5)

I believe the answer is:

unite

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

'possibly untie but here' is the wordplay.
'untie' anagrams to 'UNITE'.
Though, I am unsure how this is indicated.

Can you help me to learn more?

(Other definitions for unite that I've seen before include "Club together" , "old coin" , "Wed?" , "Get together" , "Link" .)

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

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