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n. Any of several single-valued or multivalued functions that are inverses of the sine function. Symbol: arcsin, sin-1

n. the inverse function of the sine; the angle that has a sine equal to a given number

"Drops of blood splash differently depending on the angle at which they strike a hard surface, and arcsine equations can be used to reconstruct the path that the blood took through the air."

trigonometric function    circular function   

inverse sine