Expected Dutch portrait painter to accommodate current king (6)
I believe the answer is:
likely
'expected' is the definition.
(synonyms)
'dutch portrait painter to accommodate current king' is the wordplay.
'dutch portrait painter' becomes 'Lely' (17th-century artist Peter Lely).
'to accommodate' indicates putting letters inside.
'current' becomes 'I' (symbol for electric current).
'king' becomes 'K' (abbreviation for king in chess).
'i'+'k'='ik'
'lely' enclosing 'ik' is 'LIKELY'.
(Other definitions for likely that I've seen before include "In all probability" , "Has a good chance of being the case" , "Quite possible" , "Such as well might happen" , "In prospect" .)