Upsilon

Greek letters
Α α Alpha;	Β β Beta;
Γ γ Gamma;	Δ δ Delta;
Ε ε Epsilon;	Ϝ ϝ Digamma;
Ζ ζ Zeta;	Η η Eta;
Θ θ Theta;	Ι ι Iota;
Κ κ Kappa;	Λ λ Lambda;
Μ μ Mu;	Ν ν Nu;
Ξ ξ Xi;	Ο ο Omicron;
Π π Pi;	Ϻ ϻ San;
Ϙ ϙ Qoppa;	Ρ ρ Rho;
Σ σ Sigma;	Τ τ Tau;
Υ υ Upsilon;	Φ φ Phi;
Χ χ Chi;	Ψ ψ Psi;
Ω ω Omega;	Ϡ ϡ Sampi;
Greek alphabet

Upsilon (upper case Υ, lower case υ) is the 20th letter of the Greek alphabet. In the system of Greek numerals it has a value of 400.