ground floor noun
plural ground floors
plural ground floors
Learner's definition of GROUND FLOOR
[count]
: the floor of a building that is at ground level底楼;底层;一楼 — called also (US) first floor
in on the ground floor
◊ If you are/get in on the ground floor of something (such as a new business or project), you become involved in it at the very beginning.在…开始阶段参与