Deer musk is a substance with a persistent odor, obtained from the caudal glands of the male musk deer.
Although more commonly referred to as "musk", the term itself is often used to describe a wide variety of "musky" substances from other animals such as the African civet ("civet musk") or various synthetic musks whose compound exhibits some character of deer musk.
The demand for deer musk has led to a severe decrease in musk deer populations; however, musk can be removed from the gland of live male deer without killing the animal and without harming their growth, breeding and health. The extraction of musk from live deer has been successfully conducted many times and the characteristics of musk have been studied at the Kathmandu Zoo in Nepal. Six of the seven musk producing species are listed as Endangered.