Mistakes resulting from inattention (6)
I believe the answer is:
lapses
'mistakes resulting from inattention' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for lapses that I've seen before include "Failures of memory" , "Failures to maintain higher states" , "Slight errors caused by forgetfulness" , "declines" , "Careless mistakes" .)