Onion (7)
I believe the answer is:
shallot
'onion' is the definition.
(I know that shallot is a type of onion)
This is the entire clue.
(Other definitions for shallot that I've seen before include "bit of salad" , "It resembles an onion" , "Small onion" , "found in the allotment" , "Type of 12" .)