Musk
late Middle English: from late Latin muscus, from Persian mušk, perhaps from Sanskrit muṣka ‘scrotum’ (because of the similarity in shape of the sac on the abdomen of a male musk deer in which musk is produced).
wiktionary
From Middle English muske, borrowed from Old French musc, from Late Latin muscus, from Ancient Greek μόσχος(móskhos), from Middle Persian[script needed](mwšk'/mušk/) whence Persian مشک (mošk). Ultimately from Sanskrit मुष्क(muṣka, “ testicle”), the shape of the gland of animals secreting the substance being compared to human testicles, a diminutive of मूष्(mūṣ, “mouse”), the shape of human testicles being compared to mice, from Proto-Indo-European *muh₂s(“mouse”). Cognate with mouse.
etymonline
musk (n.)
odoriferous reddish-brown substance secreted by the male musk deer (dried and used in medicinal preparations and as a perfume), late 14c., from Old French musc (13c.) and directly from Medieval Latin muscus, from Late Greek moskhos, from Persian mushk, from Sanskrit muska-s "testicle," from mus "mouse" (so called, presumably, for resemblance; see muscle). The deer gland was thought to resemble a scrotum. German has Moschus, from a Medieval Latin form of the Late Greek word. Spanish has almizcle, from Arabic al misk "the musk," from Persian.
The musk-deer, the small ruminant of central Asia that produces the substance, is so called from 1680s. The name musk was applied to various plants and animals of similar smell, such as the Arctic musk-ox (1744). Musk-melon "the common melon" (1570s) probably originally was an oriental melon with a musky smell, the name transferred by error [OED]. Also compare Muscovy.
