dilatant: meaning, definition, pronunciation and examples
C2Technical/Scientific
Quick answer
What does “dilatant” mean?
A substance that increases in viscosity or becomes thicker when subjected to shear stress (e.
Audio
Pronunciation
Definition
Meaning and Definition
A substance that increases in viscosity or becomes thicker when subjected to shear stress (e.g., when stirred, shaken, or impacted).
In a more general scientific or technical sense, anything that expands or widens under an applied force. Less commonly, it can describe a phenomenon or process of expansion.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or spelling. Pronunciation may follow regional patterns.
Connotations
Purely technical in both varieties.
Frequency
Extremely rare in general usage in both regions, confined to technical literature.
Grammar
How to Use “dilatant” in a Sentence
[material/substance] is dilatant[substance] exhibits dilatant propertiesthe dilatant nature of [substance]Vocabulary
Collocations
Examples
Examples of “dilatant” in a Sentence
adjective
British English
- The cornflour mixture showed a clearly dilatant response when struck suddenly.
American English
- The body armor uses a dilatant fluid that hardens on impact.
Usage
Meaning in Context
Business
Virtually never used.
Academic
Used in physics, engineering, and materials science papers to describe non-Newtonian fluids.
Everyday
Not used in everyday conversation.
Technical
Core usage domain. Describes specific materials like concentrated cornstarch-water mixtures (oobleck), some silica sands, or certain protective gear materials.
Vocabulary
Synonyms of “dilatant”
Neutral
Weak
Vocabulary
Antonyms of “dilatant”
Watch out
Common Mistakes When Using “dilatant”
- Confusing with 'dilate' (to widen) in a medical context.
- Mispronouncing as /dɪˈlætənt/ (like 'dilute').
- Using it as a general synonym for 'expanding' outside rheology.
FAQ
Frequently Asked Questions
No. While both relate to the Latin root 'dilatare' (to spread out), 'dilating' usually refers to widening (e.g., pupils dilating). 'Dilatant' is a specific technical term for a material that thickens under shear stress.
Almost never. It is a highly specialized term used mainly in rheology and materials science. In casual talk, you would describe the behavior (e.g., 'gets thicker when you stir it fast').
The opposite is a 'shear-thinning' or 'pseudoplastic' fluid, which becomes less viscous under shear stress (e.g., ketchup, paint).
No, this is a common misconception. True quicksand is often slightly dilatant initially but is primarily a liquefied material; it does not harden under rapid force like oobleck. Its behavior is more complex.
A substance that increases in viscosity or becomes thicker when subjected to shear stress (e.
Dilatant is usually technical/scientific in register.
Dilatant: in British English it is pronounced /daɪˈleɪt(ə)nt/, and in American English it is pronounced /daɪˈleɪt(ə)nt/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think: 'DILATE' + 'ANT'. An ANT trying to run across a pool of cornstarch and water (oobleck) makes it DILATE (stiffen) under its feet, trapping it—this is dilatant behavior.
Conceptual Metaphor
A crowd that becomes harder to push through the faster you try to move (shear-thickening).
Practice
Quiz
Which of the following is a classic example of a dilatant material?