Done carelessly (8)
I believe the answer is:
slapdash
'done carelessly' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for slapdash that I've seen before include "Slipshod, careless" , "Hastily and carelessly done" , "Cowboy" , "Irresponsible" , "Hasty and careless - hit and run?" .)