地ち下か１いっ階かい

noun

first basement floor; lower ground floor

Refers to the first underground level in a building, commonly used in elevator buttons, floor directories, and addresses.

• エレベーターで地ち下か１階いっかいまで降おりてください。

  Please take the elevator down to the first basement floor.

• 地ち下か１階いっかいには駐ちゅう車しゃ場じょうがあります。

  There is a parking lot on the first basement floor.