Shedding a tear about portal (4)
I believe the answer is:
gate
'portal' is the definition.
(I've seen this in another clue)
'shedding a tear about' is the wordplay.
'about' says the answer is hidden in the clue (the clue goes around or about the answer).
'GATE' can be found hidden inside 'shedding a tear'.
(Other definitions for gate that I've seen before include "Confine to college" , "Kind of door as in wall or fence" , "Entrance; street" , "Entry to arena" , "Doorway" .)