the least you can/could do

the least (one) could do

Something that someone ought to do; the very minimum someone should do. I know you're angry with your father, but he seems like he really wants to make amends. The least you could do is hear him out. A: "Thank you so much for the lovely card and wonderful bottle of wine!" B: "It was the least we could do after you took care of our pets while we were away."
See also: could, least

the (very) ˈleast you can/could do

the minimum you should do: The least you can do is apologize.‘Thank you so much for helping me.’ ‘Well, it was the least I could do.’
See also: can, could, least