Let·ter, n.
 1. A mark or character used as the representative of a sound, or of an articulation of the human organs of speech; a first element of written language.
    And a superscription also was written over him in letters of Greek, and Latin, and Hebrew.   --Luke xxiii. 38.
 2. A written or printed communication; a message expressed in intelligible characters on something adapted to conveyance, as paper, parchment, etc.; an epistle.
    The style of letters ought to be free, easy, and natural.   --Walsh.
 3. A writing; an inscription. [Obs.]
    None could expound what this letter meant.   --Chaucer.
 4. Verbal expression; literal statement or meaning; exact signification or requirement.
    We must observe the letter of the law, without doing violence to the reason of the law and the intention of the lawgiver.   --Jer. Taylor.
    I broke the letter of it to keep the sense.   --Tennyson.
 5. Print. A single type; type, collectively; a style of type.
    Under these buildings . . . was the king's printing house, and that famous letter so much esteemed.   --Evelyn.
 6. pl. Learning; erudition; as, a man of letters.
 7. pl. A letter; an epistle. [Obs.]
 8. Teleg. A telegram longer than an ordinary message sent at rates lower than the standard message rate in consideration of its being sent and delivered subject to priority in service of regular messages. Such telegrams are called by the Western Union Company day letters, or night letters according to the time of sending, and by The Postal Telegraph Company day lettergrams, or night lettergrams.
 Dead letter, Drop letter, etc. See under Dead, Drop, etc.
 Letter book, a book in which copies of letters are kept.
 Letter box, a box for the reception of letters to be mailed or delivered.
 Letter carrier, a person who carries letters; a postman; specif., an officer of the post office who carries letters to the persons to whom they are addressed, and collects letters to be mailed.
 Letter cutter, one who engraves letters or letter punches.
 Letter lock, a lock that can not be opened when fastened, unless certain movable lettered rings or disks forming a part of it are in such a position (indicated by a particular combination of the letters) as to permit the bolt to be withdrawn.
    A strange lock that opens with AMEN.   --Beau. & Fl.
 -- Letter paper, paper for writing letters on; especially, a size of paper intermediate between note paper and foolscap. See Paper.
 Letter punch, a steel punch with a letter engraved on the end, used in making the matrices for type.
 Letters of administration Law, the instrument by which an administrator or administratrix is authorized to administer the goods and estate of a deceased person.
 Letter of attorney, Letter of credit, etc. See under Attorney, Credit, etc.
 Letter of license, a paper by which creditors extend a debtor's time for paying his debts.
 Letters close or Letters clause Eng. Law., letters or writs directed to particular persons for particular purposes, and hence closed or sealed on the outside; -- distinguished from letters patent. --Burrill.
 Letters of orders Eccl., a document duly signed and sealed, by which a bishop makes it known that he has regularly ordained a certain person as priest, deacon, etc.
 Letters patent, Letters overt, or Letters open Eng. Law, a writing executed and sealed, by which power and authority are granted to a person to do some act, or enjoy some right; as, letters patent under the seal of England.  The common commercial patent is a derivative form of such a right.
 Letter-sheet envelope, a stamped sheet of letter paper issued by the government, prepared to be folded and sealed for transmission by mail without an envelope.
 Letters testamentary Law, an instrument granted by the proper officer to an executor after probate of a will, authorizing him to act as executor.
 Letter writer. (a) One who writes letters. (b) A machine for copying letters. (c) A book giving directions and forms for the writing of letters.