leave to it

leave (someone) to it

To allow someone to do something without one's involvement or interference; to withdraw from someone so they can do or finish something alone. I just had a question about the order, but I can see that you're busy, so I'll just leave you to it. We left him to it after he made it clear that he didn't need our help.
See also: leave

leave someone to it

to withdraw and allow someone to finish something alone. I hate to leave before the job is finished, but I'll have to leave you to it. I will leave them to it. I have to go home now.
See also: leave