Exactly where one's glasses go (2,3,4)
I believe the answer is:
on the nose
'exactly' is the definition.
(I know that exactly can be written as on the nose)
'one's glasses go' is the wordplay.
I cannot quite understand how this works, but
an anagram of 'one' is 'eno' which is present in the answer.
This explanation may well be incorrect...
'where' acts as a link.
Can you help me to learn more?
(Other definitions for on the nose that I've seen before include "where might a boxer's punch land?" , "There's a bridge here" , "just to take the first place" , "Nasal kind of bet on horse to finish first - precisely" , "Exactly in America" .)