Simple, being tolerant (4)
I believe the answer is:
easy
I believe this clue is a double definition.
'simple' is the first definition.
(similar in meaning)
'tolerant' is the second definition.
(thesaurus)
'being' is the link.
(Other definitions for easy that I've seen before include "Posing no difficulty" , "careful!" , "Not difficult" , "Relaxed" , "Simple (like the living in 1 across)" .)