sebum

n. oily or fatty secretion discharged from the sebaceous glands

The sebaceous glands are glands found in the skin of mammals.
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Sebum /se·bum/ the oily secretion of the sebaceous glands, composed of fat and epithelial debris. se·bum n. [more]Sebum - Community and Resources

Noun
1. the oily secretion of the sebaceous glands; with perspiration it moistens and protects the skin
(hypernym) secretion
(hyponym) smegma

n. sebum, oily or fatty secretion discharged from the sebaceous glands