Left a junior to wash and iron (7)
I believe the answer is:
launder
'wash and iron' is the definition.
(I've seen this before)
'left a junior' is the wordplay.
'left' becomes 'l' (common abbreviation).
'junior' becomes 'under' (under can mean junior or secondary).
'l'+'a'+'under'='LAUNDER'
'to' is the link.
(Other definitions for launder that I've seen before include "Led a run (anag)" , "Convert illegal funds into legal ones" , "Wash and iron linen" , "Make illegal (money) legitimate" , "Clean, clothes or mafia money" .)