melatonin
pronunciation
How to pronounce melatonin in British English:
UK 
How to pronounce melatonin in American English:
US
Word Origin
- melatonin (n.)
- 1958, from Greek melas "black, dark" (see melanin) + ending from serotonin. So called because its secretion is inhibited by sunlight.
Example
- 1. Among other roles , melatonin acts as an antioxidant .
- 2. Take a tablet of melatonin , an over-the-counter hormone that promotes sleep .
- 3. Ask your doctor about melatonin supplements .
- 4. Their hypothesis is that the hormone melatonin might have been the culprit .
- 5. Melatonin can be found in some plants such as st. john 's wort .