ENGLISH
REFERENCE

tau

n. countable
C2 Proficiency UK //tˈaʊ// tau Archaic

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.


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.

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