In the United States, ghee made from butter is often called desi ghee to distinguish it from vegetable-based substitutes; the word desi, which means something close to "countryman," always evokes a strong, authentic connection to the homeland for the Indian diaspora.
The term 'desi ghee' is not confined to the US alone. It is used in India as well. Desh = country, but desi (the adjectival form) can also connote rusticity. Similar to say, 'Country ham.' The term 'usli ghee' (usli = real or authentic, pronounced us + lee) is also used. The vegetable based substitutes are the the crisco type hydrogenated fats - vanaspati, or vanaspati ghee thanks to marketers (the term Dalda is also used - this is a trademark and has become the name for vanaspati, like the word Xerox).
'Desi' to refer to a fellow 'countryman' is a separate (usage) term among Indians (and maybe Pakistanis?)
Happy Diwali, happy Eid, happy eating!