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pen 1 (pĕn)
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n.
1. An instrument for writing or drawing with ink or similar fluid, especially:
a. A ballpoint pen.
b. A fountain pen.
c. A pen point.
d. A penholder and its pen point.
e. A quill.
2.
a. An instrument for writing regarded as a means of expression: "Tyranny has no enemy so formidable as the pen" (William Cobbett).
b. A writer or an author: a hired pen.
c. A style of writing: wrote plays with a witty pen.
3. A pen-shaped device containing something other than ink: an insulin pen; a vaporizer pen.
4. Any of various other pen-shaped devices, such as a laser pointer.
5. The chitinous internal shell of a squid.
6. A pen shell.
7. pens Archaic The primary feathers or wings of a bird.
tr.v. penned, pen·ning, pens
To write or compose: penned a letter.

[Middle English penne, from Old French, from Late Latin penna, from Latin, feather; see pet- in the Appendix of Indo-European roots.]

penner n.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
pen 2 (pĕn)
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n.
1.
a. A fenced enclosure for animals.
b. The animals kept in such an enclosure.
c. Any of various enclosures, such as a bullpen or playpen, used for a variety of purposes.
2. A roofed dock for submarines.
tr.v. penned or pent (pĕnt), pen·ning, pens
To confine in or as if in a pen. See Synonyms at enclose.

[Middle English, from Old English penn.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
pen 3 (pĕn)
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n.
A female swan.

[Origin unknown.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
pen 4 (pĕn)
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n.
Informal
A penitentiary; a prison.

[Short for PENITENTIARY.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Pen.
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abbr.
peninsula

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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