Large bag containing real dancing bear (8)
I believe the answer is:
tolerate
'bear' is the definition.
(I've seen this before)
'large bag containing real dancing' is the wordplay.
'large bag' becomes 'tote' (I've seen this before).
'containing' is an insertion indicator.
'dancing' indicates an anagram.
'real' with letters rearranged gives 'lera'.
'tote' enclosing 'lera' is 'TOLERATE'.
(Other definitions for tolerate that I've seen before include "Stomach" , "Accept or bear with" , "Put up with, permit without protest" , "Turn a blind eye to" , "Allow" .)