The limits to well-educated Scarlet Pimpernel (4)
I believe the answer is:
weed
'scarlet pimpernel' is the definition.
The answer and definition can be both plants as well as being singular nouns.
Maybe there's an association between them I don't understand?
'the limits to well-educated' is the wordplay.
'the limits to' says to hollow out the word (remove centre letters) (only the edge letters are used).
'well' becomes 'waterhole'.
'educated' becomes 'ed' (I've seen this in other clues).
'waterhole' with its centre taken out is 'we'.
'we'+'ed'='WEED'
Can you help me to learn more?
(Other definitions for weed that I've seen before include "Marijuana (slang)" , "pot" , "gone!" , "Plant growing where it is not wanted" , "Uncultivated plant" .)