1973, originally and usually in reference to a woman's sexual climax, from orgasm (n.). Related: Orgasmed; orgasming.
1680s, "sexual climax," from French orgasme or Modern Latin orgasmus, from Greek orgasmos "excitement, swelling," from organ "be in heat, become ripe for," literally "to swell, be excited," related to orge "impulse, excitement, anger," from PIE root *wrog- "to burgeon, swell with strength" (cf. Sanskrit urja "a nourishment, sap, vigor," Old Irish ferc, ferg "anger"). Also used 17c. of other violent excitements of emotion or other bodily functions.
The peak of sexual excitement, characterized by strong feelings of pleasure and bv a series of involuntary contractions of the muscles of the genitals, usually accompanied by the ejaculation of semen by the male.