[ uh-mawr-fuhs ]
/ əˈmɔr fəs /
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lacking definite form; having no specific shape; formless: the amorphous clouds.
of no particular kind or character; indeterminate; having no pattern or structure; unorganized: an amorphous style; an amorphous personality.
Petrography, Mineralogy. occurring in a mass, as without stratification or crystalline structure.
Chemistry. not crystalline.
Biology. having structural components that are not clearly differentiated, as the nuclear material in certain bacteria.



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Origin of amorphous

First recorded in 1725–35, amorphous is from the Greek word ámorphos shapeless. See a-6, -morph, -ous
a·mor·phous·ly, adverba·mor·phous·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for amorphous

/ (əˈmɔːfəs) /


lacking a definite shape; formless
of no recognizable character or type
(of chemicals, rocks, etc) not having a crystalline structure
amorphism, nounamorphously, adverbamorphousness, noun
C18: from New Latin, from Greek amorphos shapeless, from a- 1 + morphē shape
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for amorphous

[ ə-môrfəs ]


Lacking definite form; shapeless.
Lacking organization; formless.
Lacking distinct crystalline structure.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for amorphous

[ ə-môrfəs ]

Not made of crystals. Glass, amber, and plastics are amorphous substances.
Lacking definite form or shape.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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