Musk is a strong, distinctive smell that was originally produced by certain animals, particularly the male musk deer of Asia. For centuries, this scent was collected and used in perfumes because it had an unusual quality: it made other fragrances last longer and smell richer. A tiny amount of musk could transform an ordinary perfume into something memorable.

The musk deer produces this scent in a gland, and perfume makers once hunted these animals to obtain it. Today, most musk in perfumes is created artificially in laboratories, which protects the deer and costs far less. Chemists figured out how to recreate the smell without harming animals.

The word also describes similar strong, earthy smells from other sources. Musk oxen, large shaggy animals that live in Arctic regions, got their name because they produce a musky smell. Some plants create musk-like scents too. When perfume makers describe a fragrance as musky, they mean it has that warm, slightly wild, animal-like quality that makes it smell natural and grounded rather than purely sweet or floral.