- any of a class of unsaturated fatty acids that are involved in the contraction of smooth muscle, the control of inflammation and body temperature, and many other physiological functions.
- any commercial preparation of this substance.
- any of a group of potent hormone-like compounds composed of essential fatty acids and found in all mammalian tissues, esp human semen. Prostaglandins stimulate the muscles of the uterus and affect the blood vessels; they are used to induce abortion or birth
