Brought into line smoothed on all sides (7)
I believe the answer is:
dressed
'brought into line' is the definition.
('dress' can be a synonym of 'bring into line')
'smoothed on all sides' is the wordplay.
I cannot really see how this works, but
'on' could be 're' ('on' can be mean 'with reference to') and 're' is found in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for dressed that I've seen before include "Clad" , "with mayonnaise, say" , "Trimmed" , "put bandage on" , "curried" .)