τ

See also: Τ, τ., τ', and Appendix:Variations of "t"

τ U+03C4, τ GREEK SMALL LETTER TAU ← σ [U+03C3] Greek and Coptic υ → [U+03C5]

𝜏 U+1D70F, 𝜏 MATHEMATICAL ITALIC SMALL TAU ← 𝜎 [U+1D70E] Mathematical Alphanumeric Symbols 𝜐 → [U+1D710]

Translingual

When a circle's radius is 1 unit, its circumference is τ units.

Symbol

τ

1. (physics) torque
2. (physics) shear stress
3. (mathematics, neologism) An irrational constant defined as the ratio of the circumference of a circle to its radius, equal to the radian measure of a full turn; approximately 6.283185307 (equal to 2π, or twice the value of π).
4. (physics) tauon
5. (Teutonista) a voiceless dental plosive (IPA [t̪]).

See also

• τ on Wikipedia.Wikipedia

Ancient Greek

Etymology

Derived from its majuscule counterpart Τ.

Letter

τ • (t) (lowercase, uppercase Τ)

1. Lower-case tau (ταῦ), the 19th letter of the ancient Greek alphabet. It represented the voiceless unaspirated alveolar or dental plosive /t/. It is preceded by σ and followed by υ.

Derived terms

See also tau

• τ΄ (t΄), ͵τ (͵t)
• т, Т (Cyrillic)
• 𐍄 (Gothic)
• ⲧ, Ⲧ (Coptic)

See also

• (Greek-script letters) Α α, Β β, Γ γ, Δ δ, Ε ε, Ζ ζ, Η η, Θ θ, Ι ι, Κ κ, Λ λ, Μ μ, Ν ν, Ξ ξ, Ο ο, Π π, Ρ ρ, Σ σ ς, Τ τ, Υ υ, Φ φ, Χ χ, Ψ ψ, Ω ω
• (non-Classical letters) Ϝ ϝ, Ͷ ͷ, Ͱ ͱ, Ϻ ϻ, Ϙ ϙ, Ͳ ͳ
• (punctuation) · ﹔
• (diacritics) ᾿ ῾ ◌́ ◌̀ ῀ ¨

Greek

Letter

τ • (t) (lowercase, uppercase Τ)

1. The lower case letter tau (ταυ), the 19th letter of the modern Greek alphabet.

See also

• (Greek-script letters) Α α, Β β, Γ γ, Δ δ, Ε ε, Ζ ζ, Η η, Θ θ, Ι ι, Κ κ, Λ λ, Μ μ, Ν ν, Ξ ξ, Ο ο, Π π, Ρ ρ, Σ σ ς, Τ τ, Υ υ, Φ φ, Χ χ, Ψ ψ, Ω ω
• (non-Classical letters) Ϝ ϝ, Ͷ ͷ, Ͱ ͱ, Ϻ ϻ, Ϙ ϙ, Ͳ ͳ
• (punctuation) · ﹔
• (diacritics) ᾿ ῾ ◌́ ◌̀ ῀ ¨
• τ΄ (t΄)
• ͵τ (͵t)