The Collaborative International Dictionary of English v.0.48:

Pen \Pen\ (p[e^]n), n. [OE. penne, OF. penne, pene, F. penne,
   fr. L. penna.]
   1. A feather. [Obs.] --Spenser.
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   2. A wing. [Obs.] --Milton.
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   3. An instrument used for writing with ink, formerly made of
      a reed, or of the quill of a goose or other bird, but now
      also of other materials, as of steel, gold, etc. Also,
      originally, a stylus or other instrument for scratching or
      graving.
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            Graven with an iron pen and lead in the rock. --Job
                                                  xix. 24.
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   4. Fig.: A writer, or his style; as, he has a sharp pen.
      "Those learned pens." --Fuller.
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   5. (Zool.) The internal shell of a squid.
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   6. [Etymol. uncertain.] (Zool.) A female swan; -- contrasted
      with cob, the male swan. [Prov. Eng.]
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   Bow pen. See Bow-pen.

   Dotting pen, a pen for drawing dotted lines.

   Drawing pen, or Ruling pen, a pen for ruling lines having
      a pair of blades between which the ink is contained.

   Fountain pen, Geometric pen. See under Fountain, and
      Geometric.

   Music pen, a pen having five points for drawing the five
      lines of the staff.

   Pen and ink, or pen-and-ink, executed or done with a pen
      and ink; as, a pen and ink sketch.

   Pen feather. A pin feather. [Obs.]

   Pen name. See under Name.

   Sea pen (Zool.), a pennatula. [Usually written sea-pen.]
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The Collaborative International Dictionary of English v.0.48:

Name \Name\ (n[=a]m), n. [AS. nama; akin to D. naam, OS. & OHG.
   namo, G. name, Icel. nafn, for namn, Dan. navn, Sw. namn,
   Goth. nam[=o], L. nomen (perh. influenced by noscere,
   gnoscere, to learn to know), Gr. 'o`mona, Scr. n[=a]man.
   [root]267. Cf. Anonymous, Ignominy, Misnomer,
   Nominal, Noun.]
   1. The title by which any person or thing is known or
      designated; a distinctive specific appellation, whether of
      an individual or a class.
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            Whatsoever Adam called every living creature, that
            was the name thereof.                 --Gen. ii. 19.
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            What's in a name? That which we call a rose
            By any other name would smell as sweet. --Shak.
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   2. A descriptive or qualifying appellation given to a person
      or thing, on account of a character or acts.
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            His name shall be called Wonderful, Counsellor, The
            mighty God, The everlasting Father, The Prince of
            Peace.                                --Is. ix. 6.
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   3. Reputed character; reputation, good or bad; estimation;
      fame; especially, illustrious character or fame; honorable
      estimation; distinction.
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            What men of name resort to him?       --Shak.
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            Far above . . . every name that is named, not only
            in this world, but also in that which is to come.
                                                  --Eph. i. 21.
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            I will get me a name and honor in the kingdom. --1
                                                  Macc. iii. 14.
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            He hath brought up an evil name upon a virgin.
                                                  --Deut. xxii.
                                                  19.
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            The king's army . . . had left no good name behind.
                                                  --Clarendon.
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   4. Those of a certain name; a race; a family.
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            The ministers of the republic, mortal enemies of his
            name, came every day to pay their feigned
            civilities.                           --Motley.
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   5. A person, an individual. [Poetic]
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            They list with women each degenerate name. --Dryden.
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   Christian name.
      (a) The name a person receives at baptism, as
          distinguished from surname; baptismal name; in
          western countries, it is also called a first name.
      (b) A given name, whether received at baptism or not.

   Given name. See under Given.

   In name, in profession, or by title only; not in reality;
      as, a friend in name.

   In the name of.
      (a) In behalf of; by the authority of. " I charge you in
          the duke's name to obey me."            --Shak.
      (b) In the represented or assumed character of. "I'll to
          him again in name of Brook."            --Shak.

   Name plate, a plate as of metal, glass, etc., having a name
      upon it, as a sign; a doorplate.

   Pen name, a name assumed by an author; a pseudonym or nom
      de plume. --Bayard Taylor.

   Proper name (Gram.), a name applied to a particular person,
      place, or thing.

   To call names, to apply opprobrious epithets to; to call by
      reproachful appellations.

   To take a name in vain, to use a name lightly or profanely;
      to use a name in making flippant or dishonest oaths. --Ex.
      xx. 7.
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   Syn: Appellation; title; designation; cognomen; denomination;
        epithet.

   Usage: Name, Appellation, Title, Denomination. Name
          is generic, denoting that combination of sounds or
          letters by which a person or thing is known and
          distinguished. Appellation, although sometimes put for
          name simply, denotes, more properly, a descriptive
          term (called also agnomen or cognomen), used by
          way of marking some individual peculiarity or
          characteristic; as, Charles the Bold, Philip the
          Stammerer. A title is a term employed to point out
          one's rank, office, etc.; as, the Duke of Bedford,
          Paul the Apostle, etc. Denomination is to particular
          bodies what appellation is to individuals; thus, the
          church of Christ is divided into different
          denominations, as Congregationalists, Episcopalians,
          Presbyterians, etc.
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WordNet (r) 3.0 (2006):

pen name
    n 1: an author's pseudonym [syn: pen name, nom de plume]