Expedition has tough time at border on return (10)
I believe the answer is:
pilgrimage
'expedition' is the definition.
(thesaurus)
'tough time at border on return' is the wordplay.
'tough time' becomes 'grimage' (I can't explain this - if you can you should give a lot more credence to this answer).
'at' means one lot of letters go next to another (I've seen this in other clues).
'border' becomes 'lip' (I've seen this in another clue).
'on return' is a reversal indicator.
'lip' backwards is 'pil'.
'grimage' put after 'pil' is 'PILGRIMAGE'.
'has' acts as a link.
Can you help me to learn more?
(Other definitions for pilgrimage that I've seen before include "special journey?" , "Religious traveller's journey" , "What Chaucer,s travellers were engaged upon" , "Holy journey" , "Religiously inspired journey" .)