memo

1 a message on paper from one person or group to another a long series of memos between the two authors collaborating on the book Synonyms dispatch, epistle, letter, memorandum, missive, noteRelated Words billet-doux, open letter; airmail, card, electronic mail, e-mail, junk mail, mail, postal card, postcard; communication, report; encyclical

2 a usually brief written reminder taped a memo to her computer about the upcoming meeting Synonyms jotting, note, memorandum, notationRelated Words bordereau, memoir, memorial, minutes, protocol, report; line; document, writing

3 a written communication giving information or directions memos were the standard means of office communication before the arrival of e-mail Synonyms directive, memorandum, noticeRelated Words announcement, bulletin, declaration, notification, posting, proclamation, pronouncement, release; dispatch, report; edict, pronunciamento, rescript; charge, command, dictate; directions, instructions, orders, word; encyclical, epistle, jotting, letter, mail, message, missive, note, post [chiefly British]