second home

plural second homes

1. A secondary residence.
   1. country house
   2. vacation home
   3. pied-à-terre
2. A home of a close relative or friend where one spends a great deal of time or feels welcome.

   After the death of his [Verney's] first wife, he proposed to Florence Nightingale but she refused him. Later he married her sister, and for many years Claydon was Miss Nightingale's second home.

   1960 March 28, N. Caplan, “The Railway Member of Parliament”, in Railway Magazine, page 208

3. Any place where one spends a great deal of time away from one's primary home, such as an office, a remote town or a foreign country.