third workplace
n. A place a person works other than their office or home office.
Examples
2013
The third workplace, commonly called co-working space, combines the amenities and technology of a traditional office with the flexibility and lower expense of a home office.
—Nancy Crotti, “Embracing the ‘third workplace’ in the Twin Cities,” Finance & Commerce (Minneapolis, MN), November 29, 2013
2013
There is plenty of talk in alternative workspace circles about the third workplace. In other words, places [sic] to work beyond the office and the homefront.
—Jennifer LeClaire, “Do You Really Need a Third Workplace?,” A Better Office, November 21, 2013
1999 (earliest)
The Orange Studio takes the increasingly popular concept of Internet cafes a step further. It has combined the "computers and cappuccinos" concept with state-of-the-art communications equipment to create a unique kind of shop for businesses…."We wanted to create something like Cheers meets the British Airways executive lounge. We see ourselves as the third workplace outside the office and home."
—Alison Jones, “Cappuccinos and on-line chic,” Birmingham Post, October 30, 1999