With style, arrange buttonhole (6)
I believe the answer is:
waylay
'buttonhole' is the definition.
(I've seen this before)
'with style arrange' is the wordplay.
'with' means one lot of letters go next to another.
'style' becomes 'way' ('way' can be a synonym of 'style'**).
'arrange' becomes 'lay' (I've seen this before).
'way' next to 'lay' is 'WAYLAY'.
(Other definitions for waylay that I've seen before include "Intercept and detain" , "Accost" , "Intercept and attack" , "Lie in wait for and ambush" , "Stop or interrupt (someone)" .)