Curiously notices division (7)
I believe the answer is:
section
'division' is the definition.
(synonyms)
'curiously notices' is the wordplay.
'curiously' indicates anagramming the letters.
'notices' is an anagram of 'SECTION'.
(Other definitions for section that I've seen before include "Divide; part" , "unit" , "Notices (anag)" , "Segment" , "branch" .)