also: さんか
noun
mountain villa; chalet; mountain cottage
Refers to a house or retreat located in the mountains, often used for vacations or as a second home.
夏休みに山家で過ごすのが楽しみだ。
I'm looking forward to spending summer vacation at the mountain villa.
彼は都会を離れて山家に住んでいる。
He left the city and lives in a mountain cottage.
別荘 is a general term for a second home or vacation house, not necessarily in the mountains. 山家 specifically implies a mountain setting.
Compound of 山 (mountain) and 家 (house). The reading やまが is a kun'yomi compound, while さんか is the on'yomi reading.