Close to the boundary of one’s comprehension? (4)
I believe the answer is:
deep
'one's comprehension?' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'close to the boundary' is the wordplay.
'close' becomes 'ep' (I can't justify this - if you can you should believe this answer much more).
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'the' becomes 'definitearticle'.
'boundary' suggests removing the centre (I've seen 'boundaries' mean this (only the edge or boundary letters remain)).
'definitearticle' with its middle taken out is 'de'.
'ep' put after 'de' is 'DEEP'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for deep that I've seen before include "greatly involved?" , "Intense -- extreme" , "down a long way" , "(Of sound) low in pitch" , "profoundly" .)