Learn in the textbookBasic Concepts of Competitive Strategy
DefinitionCompetitive advantage (競争優位) is a favorable position in which customers choose you more readily than your rivals and you earn higher profits.
ExplanationWhatever creates that position is called a source of competitive advantage, such as a capability other firms lack or a new technology or way of working. The harder the source is for others to copy, the longer the favorable position lasts.
AnalogyIt is like holding the best ground in a territory game. As long as you can keep holding it, you stay in a position where winning comes easier.
Memory hookThe Japanese 優位 literally reads "superior position." It names where you stand in the competition, not the capability itself.