Type of silkworm? (3)
I believe the answer is:
ilk
'type' is the definition.
(ilk can mean a type or kind)
'of silkworm?' is the wordplay.
'of' says the answer is hidden in the clue.
'ILK' is hidden in the letters of 'silkworm'.
(Other definitions for ilk that I've seen before include "Kind of silks" , "A certain type of person" , "A kind of person" , "Of that kind in Kilkenny" , "Type of person similar to one already mentioned" .)