Sentimental master taking wife's place in dance held in school yard (9)
I believe the answer is:
schmaltzy
'sentimental' is the definition.
(synonyms)
'master taking wife's place in dance held in school yard' is the wordplay.
I cannot quite understand how this works, but
'master' could be 'ma' and 'ma' is found in the answer.
'school' could be 'sch' and 'sch' is located in the answer.
'yard' could be 'y' and 'y' is found in the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for schmaltzy that I've seen before include "Effusively emotional" , "over-sentimental" , "Old-fashioned and sentimental" .)