Π

Π U+03A0, Π GREEK CAPITAL LETTER PI ← Ο [U+039F] Greek and Coptic Ρ → [U+03A1]

Π

1. 

   English Wikipedia has an article on:

   Capital pi notation

   Wikipedia
   (mathematics) Product over a set of like terms:

   ${\displaystyle \prod _{n=1}^{4}n^{2}=1^{2}\cdot 2^{2}\cdot 3^{2}\cdot 4^{2}=576}$

2. (mathematics, logic, computer science) A class (in some hierarchy of formulae, like the arithmetical hierarchy or polynomial hierarchy) of those formulae whose outermost quantifiers are universal quantifiers.

• (mathematics): Though there exists a distinct code point (∏) for the purpose of the mathematical product, the upper case pi here continues to be used for convenience.

• Σ
• Π on Wikipedia.Wikipedia

From Phoenician 𐤐 (p, “pē”).

Π • (P) (uppercase, lowercase π)

1. The letter pi (πεῖ), the 16th letter of the ancient Greek alphabet.

• (Cyrillic) Π
• (Coptic) Ⲡ
• (Gothic) 𐍀

• (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) ᾿ ῾ ◌́ ◌̀ ῀ ¨

Π • (P) (uppercase, lowercase π)

1. The uppercase letter pi (πι), the 16th letter of the modern Greek alphabet.

• (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) ᾿ ῾ ◌́ ◌̀ ῀ ¨
• Π΄
• ͵Π