A sundae is an American English term for a dish of ice cream topped with garnishes including syrups, fruits, nuts, and whipped cream.
Word origins
The origin of the term is obscure; one theory is that the spelling was deliberate changed out of religious sentiment. A 1901 reference to "ice cream Sunday" served at Huyler's in New York City is one of the first occurences of the term. In the 1890s, a similar dish was apparently called "college ice" in the Massachusetts region. Also see H.L. Mencken, "The American Language," Supplement I (1945), pp.376-7.