On both sides of the Pyrenees, joiners are all the same (3)
I believe the answer is:
yet
'are all the same' is the definition.
(I've seen this in another clue)
'on both sides of the pyrenees joiners' is the wordplay.
I cannot quite see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found within the answer.
The remaining letters 'ye' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for yet that I've seen before include "in spite of that" , "Still, so far" , "To this time, nevertheless" , "Although" , "Still; however" .)