Definition of "orgiastic"

Dancing was in progress, or, rather, one of those orgiastic ceremonies which passed for dancing during this pagan period.

1919, Sax Rohmer, Dope

Gatsby believed in the green light, the orgiastic future that year by year recedes before us. It eluded us then, but that's no matter—tomorrow we will run faster, stretch out our arms farther … And one fine morning—

1925, F[rancis] Scott Fitzgerald, chapter 9, in The Great Gatsby, New York, N.Y.: Charles Scribner’s Sons, published 1953, page 182