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melanocyte
melanocyte-stimulating hormone
melanoid
melanoma
melanophore
melanosis
melanosome
melanous
melatonin
Melba sauce
Melba toast
Melbourne
Melbourne Cup
Melchite
Melchizedek
meld (1)
meld (2)
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melatonin

mel·a·to·nin [ mèllə tṓnin ]


noun 
Definition:
 
color-changing hormone: a hormone derived from serotonin and secreted by the pineal gland that produces changes in the skin color of vertebrates, reptiles, and amphibians and is important in regulating biorhythms

[Mid-20th century. Blend of melano- + serotonin]
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