1
general::
Phrase(s): in care of someone
[to be delivered to someone] through someone or by way of someone. (Indicates that mail is to be delivered to a person at some other person’s address.) • Bill Jones is living at his father’s house. Address the letter to Bill in care of Mr. John Jones. • Bill said, "Please send me my mail in care of my father at his address."
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Through someone, by way of someone, as in I sent the gift in care of your parents. This phrase indicates that something is to be delivered to someone at someone else's address. [Mid-1800s] Also see IN CHARGE, def. 3.
American Heritage Idioms