Make sure the post is 'square' to the floor. [=make sure that there is a right angle where the post and the floor meet]
I'll go on the trip if I can 'square it with' my parents. [=if my parents will agree to let me go]
Here's the rest of the money. Now we're 'square'. [=now we don't owe each other anything]
(..) (sonar pinging) Dive six - here we are again on the deck of Titanic. / miles down, meters. The pressure outside is / tons per square inch. These windows are nine inches thick. lf they go, it's sayonara in two microseconds. All right. Enough of that bullshit. Put her down on the roof (..)1997 Titanic