from wikipedia
… sudden discharge of accumulated sexual excitement during the sexual response cycle, resulting in rhythmic muscular contractions in the pelvic region characterized by sexual pleasure.[1][2] Experienced by males and females, orgasms are controlled by the involuntary or autonomic nervous system. They are usually associated with involuntary actions, including muscular spasms in multiple areas of the body, a general euphoric sensation and, frequently, body movements and vocalizations.[2] The period after orgasm (known as the refractory period) is typically a relaxing experience, attributed to the release of the neurohormones oxytocin and prolactin as well as endorphins (or “endogenous morphine").[3]
Human orgasms usually result from physical sexual stimulation of the penis in males (typically accompanying ejaculation) and of the clitoris in females.[2][4][5] Sexual stimulation can be by self-practice (masturbation) or with a sex partner (penetrative sex, non-penetrative sex, or other sexual activity).
relation with classical tantra and neo-tantra
Some practitioners of tantric sex aim to eliminate orgasm from sexual intercourse by remaining for a long time in the pre-orgasmic and non-emission state. Advocates such as Osho, claim that it eventually causes orgasmic feelings to spread out to all of one’s conscious experience. https://archive.org/details/tantraspirituali0000osho https://www.utne.com/mind-and-body/rajneesh-ze0z1609zfol/ https://academic.oup.com/california-scholarship-online/book/14536/chapter-abstract/168615051?redirectedFrom=fulltext
Advocates of tantric and neotantric sex who claim that Western culture focuses too much on the goal of climactic orgasm, which reduces the ability to have intense pleasure during other moments of the sexual experience, suggest that eliminating this enables a richer, fuller and more intense connection.[164]
various
https://www.latimes.com/health/la-he-orgasm11feb11-story.html