The word 'yak' technically refers only to the male of the species.

The domestic yak (Bos grunniens) has been essential to Himalayan life for over 4,500 years. In the Tibetan language, the distinction between sexes is vital for agriculture and trade. The male is called a 'yak' and is primarily used as a pack animal or for meat. The female is known as a 'dri' or 'nak' and is the cornerstone of the high-altitude dairy industry.A typical dri produces between 1 and 2 liters of milk daily during the peak summer months. This milk is exceptionally rich, containing roughly twice the fat content of standard cow milk. It is a critical ingredient for traditional Tibetan butter tea and various cheeses like 'chhurpi.' Because males cannot produce milk, locals often find it humorous when tourists request 'yak milk' or 'yak cheese.'This linguistic nuance is similar to the English distinction between a 'bull' and a 'cow.' However, outside of Central Asia, 'yak' has become a generic term for the entire species. Scientific studies by organizations like the International Centre for Integrated Mountain Development (ICIMOD) highlight how these animals are uniquely adapted to altitudes above 3,000 meters. Their physiology allows them to thrive where oxygen is thin and temperatures drop below -40 degrees Celsius.