to disappear into; to be lost in; to slip into; to get mixed in among / to do something under the cover of (confusion, etc.) / to be almost indistinguishable; to be confusingly similar

Hamilton (the capital city of Bermuda) / Hamilton (a large port city in Ontario, Canada)

(Hachijō) one's back

A type of private courier service that delivers small packages or documents to a recipient's mailbox.