What does "chi" mean and come from in "chi-squared distribution"? Does "chi" mean a random variable with a standard normal distribution? Thanks!
Chi is a Greek letter. The canonical modern history references are Karl Pearson's introduction of the chi-square test in 1900 and R.A. Fisher's work in 1924, but there is ancient history too: F.R. Helmert in 1876 deserves more than a nod.
http://jeff560.tripod.com/c.html is a good start, especially if other historical bits and pieces are of interest. It includes links. Books such as Anders Hald's histories say more.
Chi appears to be just notation that Pearson used.