More than one artist in pull-out (6)
I believe the answer is:
plural
'more than' is the definition.
(I've seen this before)
'one artist in pull-out' is the wordplay.
'one artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'in' is an insertion indicator.
'out' indicates an anagram (out can mean wrong or inaccurate).
'pull' is an anagram of 'plul'.
'ra' placed within 'plul' is 'PLURAL'.
(Other definitions for plural that I've seen before include "Word usually ending in 's'" , "Words such as "sheep" and "deer" (but not "cat" and "dog") can be this" , "Word form denoting more than one is involved" , "rivers, for example" , "Form of noun or verb in respect of more than one" .)