That which drifts in with the return of a wild predator (6)
I believe the answer is:
inflow
'that which drifts' is the definition.
I can't judge whether this defines the answer.
'in with the return of a wild predator' is the wordplay.
'with' is a charade indicator (letters next to each other).
'the return of' shows that the letters should be reversed in order.
'a wild predator' becomes 'wolf' (I am not sure about the 'wild' bit.).
'wolf' in reverse letter order is 'flow'.
'in'+'flow'='INFLOW'
Can you help me to learn more?
(Other definitions for inflow that I've seen before include "Movement inwards" , "Island of Tanzania" , "Movement (of money/people) into a place" , "Fluid movement" , "Influx" .)