Show weariness, encountering a long tale (4)
I believe the answer is:
saga
'long tale' is the definition.
(I've seen this before)
'show weariness encountering a' is the wordplay.
'show weariness' becomes 'sag' (I've seen this in another clue).
'encountering' is a charade indicator (letters next to each other).
'sag'+'a'='SAGA'
(Other definitions for saga that I've seen before include "Chronicle; adventure" , "Norse narrative" , "long series of events" , "Epic tale" , "Account of great heroism" .)