Become weary of what has some sort of merit (4)
I believe the answer is:
tire
'become weary' is the definition.
(I've seen this before)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for tire that I've seen before include "Become weary" , "Exhaust" , "Fatigue" , "Grow weary of rithe" , "Grow weary of rite" .)