Part company in Croatian port (5)

I believe the answer is:

split

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'croatian port' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for split that I've seen before include "Mediterranean port" , "Divide into portions" , "Cause fission of (atom)" , "Break in pieces - leave" , "Fork" .)

I've seen this clue in The Telegraph.

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