In the era of globalization and the deregulation of the air transportation industry, public and private stakeholders have been increasingly interested in making airports attractive for passengers and airlines. Multiple service-like indicators (i.e., satisfaction, experience, liking, and quality of service) have been used to evaluate transportation infrastructure and systems, including airport terminals. Despite literature providing a clear definition of the different indicators separately, the similarities and differences are not clear, nor is it clear whether they are equivalent and could be used interchangeably. The purpose of this paper is to further understanding of the roots and essence of the four frequently used service indicators (SIs) in airport terminals—namely satisfaction, liking, quality of service, and experience—by comparing regressors. Using a travelers’ perception survey ( N = 377) at the domestic terminal in Bogotá’s El Dorado Airport, we found that, despite their correlation, the four service proxies were, in essence, different from each other conceptually, meaning that they have to be carefully chosen for the successful evaluation of a terminal. Each SI comprises different categories, representing a unique user perception. Recognizing and acknowledging that all these terms are different furthers the transparency in defining what each indicator measures.