Kind of edible oil (6)
I believe the answer is:
sesame
'kind of edible oil' is the definition.
(oil from sesame seeds)
This is the entire clue.
(Other definitions for sesame that I've seen before include "Open ...... is magic phrase for opening door in pantomime" , "Plant grown for its seeds" , "Open ...... is magic phrase for obtaining access" , "Plant yielding seeds used for flavouring bread" , "Opening word for a magician" .)