Joshi is a family name common in India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and Nepal

Nepal

Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...

. Whereas the Joshi's of India are of Brahmin

Brahmin

Brahmin Brahman, Brahma and Brahmin.Brahman, Brahmin and Brahma have different meanings. Brahman refers to the Supreme Self...

 origin, the Joshi's of Nepal

Nepal

Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...

 are either Newars

Newa people

The Newa , Newār or Newāl) are the indigenous people and the creators of the historical civilization of Nepal's Kathmandu Valley. The valley and surrounding territory have been known from ancient times as Nepal Mandala, its limits ever changing through history.Newas have lived in the Kathmandu...

 (Tibeto-Burman Origin) or Khas-Brahmin

Brahman-Hill

The Brahman-Hill or Khas Bahun is the colloquial Nepali term for a member of the hill or mountain Brahmin caste, the traditional caste of educators, scholars and priests in Hinduism. This ethnic group of Nepal makes up 12.5% of the country's population....

 (Indo-European Origin). They have dissected to large tribes in Maharashtra and Karnataka where they are also termed under Nomadic Tribes.
The word Joshi is derived from the Sanskrit

Sanskrit

Sanskrit , is a historical Indo-Aryan language and the primary liturgical language of Hinduism, Jainism and Buddhism.Buddhism: besides Pali, see Buddhist Hybrid Sanskrit Today, it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand...

 word "Jyotishi" meaning a practitioner of Jyotish (Astrology

Astrology

Astrology consists of a number of belief systems which hold that there is a relationship between astronomical phenomena and events in the human world...

) i.e.