[mass noun] A hormone released by the pituitary gland that causes increased contraction of the uterus during labour and stimulates the ejection of milk into the ducts of the breasts.
- ‘There, hormones called prolactin and oxytocin are released into the bloodstream.’
- ‘Suckling causes the mother's pituitary gland to release two hormones, oxytocin and prolactin.’
- ‘Another chemical, the hormone oxytocin, is associated with both sexual activity and maternal bonding in humans.’
- ‘But oxytocin is also the hormone of affiliation.’
- ‘The plan was to use a gradually increasing concentration of oxytocin in order to stimulate uterine contractions.’
1920s: from Greek oxutokia sudden delivery (from oxus sharp + tokos childbirth) + -in.