Nucleus (4)
'nucleus' is the definition.
(I know that nucleus can be written as core)
This is the entire clue.
(Other definitions for core that I've seen before include "essential element" , "Central or most important part of something" , "The centre of an object" , "The centre part, as of an apple" , "Centre, heart" .)
'nucleus' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for kernel that I've seen before include "Edible seed of nut" , "Essential part" , "Inner part of nut" , "soft heart" , "Nut's centre" .)