ground zero noun
[noncount] 1 : the point on the earth's surface directly above, below, or at which an explosion (especially a nuclear explosion) occurs 2 : the central point in an area of fast change or intense activity
▪ ground zero in the battle over immigration laws 3 : the beginning state or starting point
▪ We're going to have to go right back to ground zero [=square one] and start all over again.
▪ ground zero in the battle over immigration laws
▪ We're going to have to go right back to ground zero [=square one] and start all over again.
