ground floor
1 floor of a building at ground level, not upstairs 建筑物与地面相平的一层; 一楼
[attrib 作定语]
at ground-floor level 与一楼地面相平
a,ground-floor `flat 一楼的单元. =>Usage at floor1 用法见floor1.
2 (idm 习语) be/get in on the ground `floor (infml 口) join an enterprise at its beginning （在一企业开创时）加入其中.