Eg Rosemary’s part of Wetherby (4)
I believe the answer is:
herb
'eg rosemary's' is the definition.
(rosemary is a kind of herb)
'part of wetherby' is the wordplay.
'part of' indicates a hidden word.
'HERB' can be found hidden inside 'wetherby'.
(Other definitions for herb that I've seen before include "Thyme, for example" , "bay perhaps" , "Bouquet garni component" , "Plant used in cooking" , "Parsley, for instance" .)