pied-à-terre
Concise Oxford English Dictionary © 2008 Oxford University Press:
pied-à-terre /ˌpjeɪdɑːˈtɛː/
▶noun (pl. pieds-à-terre pronunc. same) a small flat, house, or room kept for occasional use.
– origin C19: Fr., lit. ‘foot to earth’.
'pied-à-terre' also found in these Oxford entries:

