Memory

Definitions:

I went to a bunch of different sites and found out that there are multiple definitions of the word "definition" and, more importantly, it's not the differences but waht each definition highlights that is intersting about it.  Here is small table:

Source	1	2	3	4
Collins English Dictionary	1. a formal and concise statement of the meaning of a word, phrase, etc	2. the act of defining a word, phrase, etc	3. specification of the essential properties of something, or of the criteria which uniquely identify it	4. the act of making clear or definite
The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009.	1. a. A statement conveying fundamental character. b. A statement of the meaning of a word, phrase, or term, as in a dictionary entry.	2. The act or process of stating a precise meaning or significance; formulation of a meaning.	3. a. The act of making clear and distinct: a definition of one's intentions. b. The state of being closely outlined or determined: "With the drizzle, the trees in the little clearing had lost definition" (Anthony Hyde). c. A determination of outline, extent, or limits: the definition of a President's authority.	4. a. The clarity of detail in an optically produced image, such as a photograph, effected by a combination of resolution and contrast. b. The degree of clarity with which a televised image or broadcast signal is received.
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing	a defining or being defined	a statement of what a thing is	a statement of the meaning as of a word or phrase	a putting or being in clear, sharp outline
Dictionary.com Unabridged. Random House, Inc. 12 Sep. 2011	1. the act of defining  or making definite,  distinct, or clear.	2. the formal statement of the meaning or significance of a word, phrase, idiom, etc., as found in dictionaries. An online dictionary resource, such as Dictionary.com, can give users direct, immediate access to the definitions of a term, allowing them to compare definitions from various dictionaries and stay up to date with an ever-expanding vocabulary.	3. the condition of being definite,  distinct, or clearly outlined.	4. Optics . sharpness of the image formed by an optical system.

What this reveals is that there is tendency by the dictionaries to highlight the "definite" as in specific and particular notion of definition and not he elment Postman wants us to highlight--the idea taht defintiions are changeable based on the world we are living in.