Some herbal mixture or ointment (4)
I believe the answer is:
balm
'ointment' is the definition.
(synonyms)
'some herbal mixture or' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'BALM' is hidden within 'herbal mixture or'.
(Other definitions for balm that I've seen before include "'Ointment, salve (4)'" , "Aromatic herb" , "Soothing medicine for lamb" , "Royal holiday residence on the River Dee" , "that will soothe the skin" .)