You're thinking of chi (χ), not xi (ξ) which is "ksai" or "zai". https://en.wikipedia.org/wiki/Xi_(letter) https://en.wikipedia.org/wiki/Xi_(letter) Xi the su

You're thinking of chi (χ), not xi (ξ) which is "ksai" or "zai". https://en.wikipedia.org/wiki/Xi_(letter) https://en.wikipedia.org/wiki/Xi_(letter) Xi the surname is closer to "shee" when pronounced in English.