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Plagiarism: Overview

Definitions, types, and avoidance techniques

Subject Guide

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Frances Marshall
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The Oxford English Dictionary, or OED, defines plagiarism as

" 1. The action or practice of taking someone else's work, idea, etc., and passing it off as one's own; literary theft."

           Plagiarism. (2011).  Oxford University Press. Retrieved Feb 27, 2012 from  <>


This is a good, standard definition of the word, but "literary theft" is a little narrow in scope. So, for the purposes of this discussion, let's broaden the scope to include all forms of intellectual property.


Intellectual property, as defined by the US government on, is "any innovation, commercial or artistic, or any unique name, symbol, logo or design used commercially."

Intellectual Property, What Is It? (n.d.) . Retrieved  from International Trade Administration, US Department of Commerce  website:

Copyrights, trademarks, and patents are the legal protections granted to idea originators by the government.

For more coverage of copyright and fair use of information, see our libguide


Plagiarism is considered a form of academic dishonesty at Shepherd University. Academic dishonesty and its consequences are further discussed in the Academic Consequences section of this libguide.

No Citation Necessary?

The two sets of ideas that do not require citation are those which are deemed common knowledge and those that are original thoughts of the writer.


Common knowledge (like the sun rises in the East) is known by almost everyone, is usually factual (dates, persons, and the like) and can be found in non-subject specific reference works. As a note, common knowkedge can change from subject area to subject area and as new information becomes available. If uncertain whether a fact, date or piece of information is common knowledge, cite it.



Original thoughts are the ideas, hypotheses, concepts or works you as the writer, artist, inventor or theorist create. These  unique ideas and perspective define and shape your particular communication style and are, in fact, what your professors (and researchers) look for most in an essay, a paper, or a project. 

An exception to this particular rule on original thoughts or ideas not requiring citation exists, of course. (Just like in English grammar, there is almost always an exception to every rule of usage.)




While an author's original thoughts do not need to be cited, if  you wish to use the same ideas, phrasing, or quote from  published work (this includes anything previously turned in for another class or class portion), that work must be cited--because the work is no longer original. (Self-plagiarism is still plagiarism and is handled accordingly.) If uncertain about the re-use of any previously published work in your papers or projects, talk with your professor beforehand--and cite your own work in the new assignment if it is used as a source.