amorphous
Americanadjective
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lacking definite form; having no specific shape; formless.
the amorphous clouds.
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of no particular kind or character; indeterminate; having no pattern or structure; unorganized.
an amorphous style; an amorphous personality.
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Petrography, Mineralogy. occurring in a mass, as without stratification or crystalline structure.
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Chemistry. not crystalline.
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Biology. having structural components that are not clearly differentiated, as the nuclear material in certain bacteria.
adjective
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lacking a definite shape; formless
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of no recognizable character or type
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(of chemicals, rocks, etc) not having a crystalline structure
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Not made of crystals. Glass, amber, and plastics are amorphous substances.
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Lacking definite form or shape.
Other Word Forms
Etymology
Origin of amorphous
First recorded in 1725–35, amorphous is from the Greek word ámorphos shapeless. See a- 6, -morph, -ous
Explanation
Amorphous means without a clearly defined form, like the moon's amorphous reflection in a lake. Figuratively, something amorphous lacks focus, be it a work of art, a political movement, or even someone's life plans. The Greek roots of this word are clear: morphē means "form," and a- means "lacking or without." When creative works or ideas are described as amorphous, it means they suffer from a lack of organization. An amorphous object lacks a well-defined outline or structure, like amorphous jellyfish drifting on the surface of the ocean. And scientifically, this adjective simply describes something without a crystalline form, like an amorphous metal or amorphous ice.
Vocabulary lists containing amorphous
100 SAT Words Beginning with "A"
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300 Most Difficult "SAT" Words
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The Great Gatsby
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Made from amorphous silica, a form of silicon dioxide found naturally in foods and the fossilized remains of microscopic organisms, the engineered nanoparticles appear to attack prostate cancer in multiple ways at once.
From Science Daily ● Jul. 9, 2026
Previous efforts have explored alternatives including polycrystalline silicon, amorphous and nanocrystalline metal oxides, carbon nanotubes, and two-dimensional semiconductors.
From Science Daily ● May 30, 2026
“There’s no historical precedent in modern California history for a governor’s race with such a large field or such an amorphous field of candidates,” said longtime political observer Dan Schnur.
From Los Angeles Times ● Mar. 26, 2026
Robe says she chose the off-white Crate & Barrel center table for its 'organic, amorphous shape.'
From The Wall Street Journal ● Mar. 7, 2026
A new world, material without being real, where poor ghosts, breathing dreams like air, drifted fortuitously about . . . like that ashen, fantastic figure gliding toward him through the amorphous trees.
From " The Great Gatsby" by F. Scott Fitzgerald
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
