Small section of verse also fine on reflection (4)
I believe the answer is:
foot
'small section of verse' is the definition.
(as in metrical feet in poetry)
'also fine on reflection' is the wordplay.
'also' becomes 'too' (synonyms).
'fine' becomes 'f' (abbreviation).
'on reflection' says the letters should be written in reverse.
'too'+'f'='toof'
'toof' in reverse letter order is 'FOOT'.
(Other definitions for foot that I've seen before include "support" , "Metrical unit; pay (a bill)" , "Labour Party leader, 1980-83" , "Infantry - unit of linear measure" , "Unit of length" .)