In the middle, we note that outside may be bent (7)
I believe the answer is:
between
'in the middle we note that outside may be bent' is the definition.
'between' can be an answer for 'in the middle' (I've seen this before). I am not sure about the rest of the definition.
'in the middle we note that outside may be' is the wordplay.
'in the middle' becomes 'bet' (I can't justify this - if you can you should believe this answer much more).
'that outside' says to hollow out the word (remove centre letters).
'may be' is an anagram indicator.
'note' with its middle taken out is 'ne'.
'ne' with letters rearranged gives 'en'.
'bet'+'we'+'en'='BETWEEN'
Can you help me to learn more?
(Other definitions for between that I've seen before include "Amid" , "Don't tell anyone else..." , "Don't tell anybody else!" , "In the interval" , "Betwixt" .)