A pile of snow moving aimlessly (6)
I believe the answer is:
adrift
'aimlessly' is the definition.
(I've seen this in another clue)
'a pile of snow moving' is the wordplay.
I cannot really understand how this works, but
'a' is present in the answer.
The remaining letters 'drift' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for adrift that I've seen before include "(Of boat) moving out of control" , "Floating uncontrolled" , "without purpose or direction" , "cut loose" , "Unsettled or unanchored" .)