none of your business; mind your own business; keep out of it
A set phrase used to reject unwanted meddling or advice, often with irritation. The お世話 is ironic, implying the help is not appreciated.
"You should study more." "Mind your own business!"
His advice was completely unwelcome.
お世話 normally means help or care, but in 大きなお世話 it is used ironically to mean unwanted interference.
Standard spelling; お世話 is used ironically.
Variant with honorific 御; less common.
A fixed expression combining 大きな (big) and お世話 (help/care), where お世話 is used ironically to mean meddling or unwanted concern.