The article suggests a new way to define loss aversion in decision-making. It proposes that people dislike taking equal bets where they could either win or lose, and this dislike grows with the size of the bet. The study introduces weak and strong forms of loss aversion, similar to risk aversion. It shows that loss aversion is not the same as having a specific shaped utility function in decision theory. The findings also suggest a method to measure loss aversion in preferences that follow certain rules. The study extends previous work by other researchers and explores how different theories of decision-making relate to loss aversion.