what does c/o mean on a letter
Best Answer: c/o means care of, used when there is an intermediary that will distribute your letter or package. You should address your letter Millvina Dean c/o Titanic Historical Society. Source(s): http://en.wiktionary.org/wiki/care_of.BabyGirlK Â· 8 years ago.eport Abuse. On the envelope you would write the person's name on the first line, and c/o the society on the second. The mail carriers read from bottom up.