A "bicycle built for twos" is a unique type of bicycle designed specifically for two passengers. It is an ideal choice for couples or friends who wish to travel together on a single bicycle. There are several synonyms for a "bicycle built for twos" with each denoting a slightly different style. Tandem bike and tandem bicycle are the most commonly used synonyms for this unique bicycle model. Additionally, some refer to it as a two-seater, two-up or double bike. Regardless of its name, this unique bicycle brings two people closer together and allows them to experience the joys of cycling while enjoying each other's company.