One-one; close (4)
I believe the answer is:
mean
'close' is the definition.
(I've seen this before)
'one-one' is the wordplay.
'one' becomes 'me' (a setter might use 'one' to humourously mean 'me').
'one' becomes 'an' (I've seen this in other clues**).
'me'+'an'='MEAN'
(Other definitions for mean that I've seen before include "Relating to flowers" , "Close" , "Base; tight" , "Intend; not generous" , "Stingy; Scrooge-like" .)