Cold sheets can be synonymous to several words depending on the context. In a medical perspective, it can be referred to as hypothermia. In a literal sense, it may be exchanged with frigid or chilly, while in a figurative application, it can signify detachment, aloofness, or isolation. Other than that, it can also connote discomfort and unease, and can be synonymous with phrases such as "cold sweat" or "cold feet." In addition, colloquially, it can express a sense of disappointment or negative connotation, which can be interchangeably replaced with expressions such as "bummer" or "downer." Therefore, using the appropriate synonym will rely on how it is generally conveyed and what best fits the context.