Wise man's flavouring (4)
I believe the answer is:
sage
This clue is a triple definition!
'wise' is the first definition.
(similar in meaning)
'man's' is the second definition.
(I have seen 'Wise man' mean 'sage' so perhaps 'man' could also mean 'sage')
'flavouring' is the third definition.
(sage is a kind of flavouring)
(Other definitions for sage that I've seen before include "Culinary herb" , "Solon, for instance" , "Fragrant herb having wisdom" , "Herb used in cooking" , "A herb or a guru" .)