Tolerate, endure (4)
I believe the answer is:
bear
I believe this clue is a double definition.
'tolerate' is the first definition.
(synonyms)
'endure' is the second definition.
(I know that endure can be written as bear)
(Other definitions for bear that I've seen before include "Carry; large mammal" , "stand" , "Show" , "Carry; brutish person" , "Give birth to; animal" .)