Understanding it's close enough to see (7)
I believe the answer is:
insight
'understanding' is the definition.
(I know that insight is a type of understanding)
'close enough to see' is the wordplay.
'close enough' becomes 'in' (I can't explain this - if you can you should believe this answer much more).
'to see' becomes 'sight' (I've seen this before).
'in'+'sight'='INSIGHT'
'it's' is the link.
Can you help me to learn more?
(Other definitions for insight that I've seen before include "ability to perceive clearly" , "Furniture from Princes Street for" , "Acute understanding" , "Visible" , "Imaginative penetration" .)