The term "arcsin" is the inverse function of "sin." This means that if we take the sine of an angle and use the "arcsin" function, we can find the original angle that produced that sine value. However, there are several other synonyms for "arcsin." Some of these include "inverse sine," "sin^-1," "sine inverse," and "arc sine." These synonyms are often used interchangeably in mathematics and are all used to denote the inverse function of the standard sine function. Regardless of the terminology used, the arcsin function remains a critical tool in trigonometry and other areas of mathematics.