Crossword Genius

Whence to sail back from the tropics (4)

Ross

I believe the answer is:

port

I'm a little stuck... Click here to teach me more about this clue!

But I can't explain it at all! Could you help me understand?

(Other definitions for port that I've seen before include "Anchorage" , "where one would expect water" , "Drink passed to the left" , "'Any . . . . In a storm'" , "Stanley perhaps" .)

Want a hint initially instead of a full solution? Install my app