This expression refers to raising Euler's number ($e$) to the power of sine evaluated at x. It results in an exponential function that oscillates between values close to 1 and -1.
Related terms
Euler's Number ($e$): A mathematical constant approximately equal to 2.71828, often used in exponential functions and calculus.
Sine Function: A trigonometric function that relates angles in a right triangle with ratios of side lengths.