English Reference

Word

tau

UK/tˈaʊ/

Definition

n. the 19th letter of the Greek alphabet. In science and math, it often represents a specific number or a type of tiny particle.

n. the nineteenth letter of the Greek alphabet, represented as τ. In physics, it denotes a specific elementary particle (the tau lepton), while in mathematics, it is frequently used to represent the circle constant equal to 2π.

Examples

“The scientist used the symbol tau in her equation.”

“In many modern geometry circles, mathematicians prefer using tau instead of pi because it represents a full turn around a circle.”

“The discovery of the tau lepton provided crucial evidence for the third generation of fundamental particles in the Standard Model of particle physics.”

Examples

simple

“The scientist used the symbol tau in her equation.”

contextual

“In many modern geometry circles, mathematicians prefer using tau instead of pi because it represents a full turn around a circle.”

complex

“The discovery of the tau lepton provided crucial evidence for the third generation of fundamental particles in the Standard Model of particle physics.”

Usage

When referring to the mathematical constant, it is often treated as an uncountable abstract concept.

Real-World Examples

“Until recently, diagnosing Alzheimer’s required a medical history and exam as well as postmortem evidence of two abnormal proteins associated with the disease called amyloid and tau .”
The Conversation · 26 Aug 2026
“Hormone therapy use was linked to 39% lower odds of a dementia diagnosis and 35% lower odds of Alzheimer’s-related brain changes at autopsy, including amyloid plaques and tau tangles.”
ScienceDaily · 14 Aug 2026

Domains

AstronomyFinanceMathematicsMedicine

This entry

Level
C2 · Proficiency
Frequency
Frequent
Updated

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English Reference