Definition – What does Squaring Up mean?
Squaring up is a slang term for when a trader closes an open position. If a position is at a loss, a trader must pay to square it up. If a trader has no open positions in the market, he or she is referred to as being square.
ForexTerms explains Squaring Up
Squaring up is simply another way to say that a trade is being settled. For example, a day trader usually squares up on all the open trades before the market closes. This way the trader is square (no trades open) overnight and ready to start fresh in the morning.