1680s, "sexual climax, the acme of venereal excitement," 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" (source also of Sanskrit urja "a nourishment, sap, vigor," Old Irish ferc, ferg "anger"). Also used 17c. of other violent excitements of emotion or other bodily functions; broader sense of "immoderate excitement or action" is from 1763.
1973, originally and usually in reference to a woman's sexual climax, from orgasm (n.). Related: Orgasmed; orgasming.