n.
distance from the top to bottom
distance from front to back
1) in ~ (the river is thirty feet in ~)
place at the bottom of a body of water
2) to reach a ~ (the divers reached great ~s)
capability
3) beyond, out of one's ~
worst part
4) in the ~s (in the ~s of the depression)
misc.
5) in ~ ('thoroughly'); to plumb the ~s of smt. ('to get to the root of smt.'); in the ~s of despair; to lack ~ ('to be superficial')