n.
1) to attain, reach a ~
2) to clear; scale a ~
3) a dizzy, precipitous, vertiginous ~; dizzying ~s
4) a ~ above; below (at a ~ of two hundred feet above sea level)
5) at a ~ (at the ~ of one's success; to fly at a ~ of ten thousand feet)
6) in ~ (ten feet in ~)